Anti-TCR delta chain variable region 1 antibody

Abstract

The present invention provides high affinity anti-TCR delta variable region 1 (anti-V delta 1) antibodies and antibody fragments thereof. The present invention also provides compositions and pharmaceutical compositions comprising such antibodies, as well as methods for producing such antibodies. The present invention also provides methods of therapeutic and medical use comprising the antibodies.

Description

[Technical Field]

[0001] The present invention relates to antibodies that specifically bind to the T cell receptor of γδ T cells, as well as fragments and variants thereof. [Background technology]

[0002] Growing interest in T cell immunotherapy for cancer has focused on the apparent ability of CD8+ and CD4+ αβ T cell subsets to recognize cancer cells and mediate host-protective functions, particularly when derepressed by clinically relevant antagonism of inhibitory pathways exerted by PD-1, CTLA-4, and other receptors. However, αβ T cells are MHC-restricted, which can lead to graft-versus-host disease.

[0003] Gamma delta T cells (γδ T cells) are a subset of T cells that express a distinct, distinctive γδ T cell receptor (TCR) on their surface. This TCR is composed of one gamma (γ) chain and one delta (δ) chain, each of which undergoes chain rearrangement. However, compared to αβ T cells, these cells have a limited number of V genes. The main TRGV gene segments encoding Vγ are TRGV2, TRGV3, TRGV4, TRGV5, TRGV8, TRGV9, and TRGV11, as well as nonfunctional genes TRGV10, TRGV11, TRGVA, and TRGVB. The most common TRGV gene segments encode Vδ1, Vδ2, and Vδ3, with several V segments designated both Vδ and Vα (Adams et al., 2015, Cell Immunol., 296:30-40). Human γδ T cells can be broadly classified based on their TCR chain, as particular γ and δ types are widely, but not exclusively, found in cells of one or more tissue types. For example, most blood-resident γδ T cells express Vδ2 TCRs, commonly Vγ9Vδ2, whereas this is less common in tissue-resident γδ T cells, e.g., those in the skin, which more frequently use Vδ1 TCRs paired with a γ chain, e.g., Vδ1 TCRs paired with Vγ4 in the gut.

[0004] γδ T cells play a key role in immune surveillance, recognizing malignant or transformed cells (such as cancer cells) by their stress marker patterns and then exerting potent and selective cytotoxicity. Thus, γδ T cells can act as orchestrators of the immune response. In situ modulation of these cells offers the potential for increased immunogenicity, even in tumors with low mutational burdens, which have proven challenging for other immunotherapies. γδ T cell recognition of tumors is not dependent on any single tumor antigen; therefore, modulators of γδ T cells have potential in a wide range of disease indications, including both hematological and solid malignancies. The recognition mechanism of γδ T cells is not MHC-restricted.

[0005] The authors of WO2019147735 hypothesize that some gamma delta cells have tumor-promoting activity or inhibit anti-cancer immune responses mediated by alpha beta T cells. They hypothesize that gamma delta T cells are immunosuppressants and therefore propose that they should be eliminated, inhibited, or blocked using antibodies in cancer.

[0006] However, despite the prevailing view that anti-γδ antibodies negatively regulate the function of γδ cells by blocking or killing such cells, a positive correlation has been found between γδ T cell infiltration and patient prognosis and / or survival.

[0007] Compared to the αβ TCR receptor / ligand interaction, our understanding of the vδ1 TCR receptor / ligand interaction is limited. Due to this lack of understanding, antibodies recognizing the vδ1 TCR to date have primarily been exploratory tools for investigating this interaction. Typically, these tools are crude blocking antibodies that suggest that the TCR receptor / ligand interaction results in the blocking, suppression, or elimination of vδ1+ cells. For example, the tool antibodies TS8.2 and TS-1 have been used as anti-γδ blocking antibodies in studies suggesting that they reduce the cytotoxicity of vδ1 cells. These studies, combined with others, suggest that such anti-vδ1 antibodies cannot be used to favorably modulate vδ1 cell cytotoxicity in in situ disease, thus suggesting the need for antibodies that increase, rather than decrease, vδ1 cytotoxicity.

[0008] To utilize γδ T cells for immunotherapy, either a means to expand the cells in situ or a means to harvest and expand them ex vivo before reinfusion is required. The latter approach, which utilizes the addition of exogenous cytokines, has been previously described. See, for example, WO2017 / 072367 and WO2018 / 212808. Methods for expanding a patient's own γδ T cells using pharmacologically modified forms of hydroxymethylbut-2-enyl pyrophosphate (HMBPP) or clinically approved aminobisphosphonates have been described. These approaches have seemingly safely treated over 250 cancer patients, although complete remissions are extremely rare. However, there remains a need for activating agents with a proven ability to expand large numbers of γδ T cells.

[0009] Furthermore, binders or activators that can preferentially target, bind to, recognize, specifically modulate, or increase the number of V51+ cells in situ in vivo may be highly desirable as pharmaceutical agents.

[0010] However, although drugs exist that may modulate V52+ cells, including aminobisphosphonates such as Zometa® (zoledronic acid), these medications are primarily designed to slow bone resorption. Despite this modulation of V52+, there is a need to develop medications specifically designed to bind, target, modulate, activate, or increase the number of V51+ cells, for example, because repeated modulation of V52+ may result in a persistent and progressive exhaustion phenotype.

[0011] Furthermore, given that V51+ cells are primarily tissue-resident, an ideal drug capable of modulating V51+ would also exhibit fewer undesirable "off-target" effects and rapid renal clearance. Typically, these undesirable effects can manifest when using small molecule chemicals. For example, the aforementioned aminobisphosphonates, which have been shown to modulate a distinct class of V52+ cells (secondary to their primary regulatory effect on bone), are associated with nephrotoxicity, manifested as worsening renal function and potentially renal failure (e.g., Markowitz et al. (2003) Kidney Int. 64(1):281-289). Additional undesirable effects of Zometa listed by the European Medicines Agency include anemia, hypersensitivity reactions, hypertension, atrial fibrillation, muscle pain, general pain, fatigue, increased blood urea, vomiting, joint swelling, and chest pain.

[0012] The in situ environment in which vδ1+ cells are found must also be considered. For example, it has previously been shown that nonhematopoietic tissue-resident γδ T cells exhibited robust proliferative responses when initially isolated from tissue, but only in the absence of direct cell-cell contact with autologous fibroblasts. It has been discovered that nonhematopoietic tissue-resident T cells (γδ T cells) must be separated from nonhematopoietic cells (e.g., stromal cells, particularly fibroblasts) to function. This is because direct contact of lymphocytes with stromal or epithelial cells appears to inhibit the proliferation of tissue-resident γδ T cells. The observation that pre-activated cells exist in a more suppressed state in situ is another reason why vδ1+ cells have not previously been considered a promising therapeutic target. Indeed, until the discoveries described herein, no method had been devised that could effectively and selectively modulate blood and tissue vδ1+ cells in situ, when these cells are typically considered to be in a "resting," "pre-activated," or "non-activated" state.

[0013] Bispecific and multispecific antibodies in various formats have been developed for various therapeutic applications. Bispecific and multispecific antibodies can be classified into overlapping yet distinct classes based on the type of biological target and mode of action. For example, such multispecific antibodies can be classified into classes such as cytotoxic effector cell redirectors (also known as bispecific T cell engaging antibodies, bispecific T cell engagers, TCEs, or BiTEs) and dual immunomodulators (DIs).

[0014] T-cell engagers (TCEs) are designed to enhance a patient's immune response against tumors by targeting T cells to tumor cells or vice versa. They function by targeting a first epitope (usually CD3) on the T-cell receptor complex of a T cell and a second epitope that is a cancer antigen or a cancer-associated antigen (TAA), such as a cancer antigen or tumor-associated antigen (TAA). Such antibodies colocalize with tumor cells and T cells to promote tumor cell killing. Examples of BiTEs include the CD3 x CD19 bispecific antibody blinatumomab, the CD3 x EpCAM bispecific antibody catumaxomab, and the CD3 x HER2 bispecific antibody ertumaxomab. TCEs, such as BiTEs, are typically provided in scFv format, although other formats are also available. For example, BiKE is similar to BiTEs but targets CD16 on NK cells instead of CD3.

[0015] The T cell receptor has been described as the most complex receptor structure in the mammalian immune system. It constitutes a transmembrane multiprotein receptor complex containing the T cell receptor in close proximity to several CD3 chains. For example, in mammals, a typical such complex contains the T cell receptor, CD3γ chain, CD3δ chain, and two CD3ε chains. These chains associate with the T cell receptor (TCR) alongside the bound ζ chain (zeta chain), which then generates the typical activation signal in T lymphocytes. However, alternative complexes have also been reported. For example, a T cell receptor complex containing the T cell receptor and a ζ chain homodimer has been described. Additional coreceptors, such as CD4 and CD8, may also support TCR function.

[0016] Regardless of the composition of the receptor complex, it is well established that the complex transduces cell surface binding events into intracellular phosphorylation signaling cascades that result in the activation of transcription factors such as NFAT and NFkB, which cause increased expression of cytokines and effector proteins such as granzymes and perforin.

[0017] However, while the use of such TCEs to treat cancer remains a compelling concept, to date, and even after 30 years of concerted efforts to advance TCEs in early clinical development, many such bispecific antibodies have demonstrated poor safety, efficacy, and manufacturability profiles. In fact, as of January 2020, the only TCE that has not been withdrawn after approval remains blinatumomab. This TCE multispecific antibody fragment binds to the T cell receptor complex with one binding arm and to the CD19 target with the second binding arm.

[0018] Bispecific T cell-engaging antibodies have been described in Lejeune et al., 2020, Front Immunol., 11:762. However, existing bispecific antibodies in this category, particularly those that engage T cells through CD3 binding, have significant off-target effects that result in severe adverse effects, given the potency of the CD3 antigen as a signaling molecule and its ubiquitous presence in patient T cell populations. Thus, for example, in the case of CD3-targeting bispecifics such as catumaxomab (now withdrawn), systemic delivery (e.g., intravenous) is practically impossible. Instead, more limited delivery, such as intraoperative, intraperitoneal, or intraperitoneal delivery, is more frequently intended. This limits the selectivity and use of these bispecifics as drugs. In fact, even anti-CD3 antibodies with attenuated effector function (i.e., T cell complex engagers that target CD3 but are not bispecific) present challenges for intravenous delivery due to associated toxicities. For example, the anti-CD3 antibody foralarumab is currently mostly intended for oral delivery (eg, in the treatment of gastrointestinal diseases) to limit exposure and reduce toxicity.

[0019] Many of the current problems observed with such TCEs in early clinical trials are often attributed to the high-affinity T cell complex binding domains used. It has been proposed that this is because the designers of these TCEs did not fully consider the low affinity of the natural TCR complex binding event, resulting in severe dose-limiting toxicities and a very narrow therapeutic window. In this regard, it has been emphasized that many early TCE drug developers relied on three anti-CD3 T cell complex binding domains derived from OKT3, SP34, and UCHT1. All of these original binding domains bind with relatively high affinities in the single- to low-double-digit nM range, equivalent to approximately 1,000-fold higher affinities than the natural binding event. As a result, it has been proposed that T cell activation is significantly different (and often unfavorable) compared to the natural T cell receptor complex binding event. For example, TCE developers using platforms based on the higher affinity OKT3 may be swayed by the fact that OKT3 induces T cell apoptosis in the presence of IL-2.

[0020] For these reasons, lower affinity T cell complex binding has emerged as an important consideration for determining the design parameters of T cell-engaging bispecific antibody therapeutics.

[0021] Another issue in designing TCEs is the need to attenuate Fc function. Indeed, because Fc binding to Fcγ receptors (FcγRs) triggers immune effector cell activation, TCEs typically require complete suppression of Fc-mediated effector functions to maximize therapeutic efficacy and minimize off-target toxicity. In fact, the majority of CD3-targeting bispecific antibodies currently used in clinical practice have Fc domains with reduced FcγR binding activity or are bispecific fragments that intentionally lack an Fc region. In general, TCEs with unattenuated Fc function are expected to induce antibody-dependent cellular cytotoxicity (ADCC), thereby depleting the γδ T cell population recognized by the antibody. However, again, attenuating such functions to avoid toxicity / safety complications, e.g., by engaging CD16+ or CD32+ or CD64+ immune cells, or by reducing the half-life of the bispecific (e.g., when using smaller bispecific antibody fragments such as BITE), may also attenuate potentially important efficacy aspects. Methods that reduce the interaction of FcγR and TCE (e.g., using IgG formats designed to reduce such interactions) are expected to reduce Fc-mediated TCE immobilization and reduce TCR clustering due to cross-linking with immobilized TCE.

[0022] To address some, but not all, of these issues, numerous companies, including Xencor (Pasadena, CA), Macrogenics (Gaithersburg, MD), and Genentech (San Francisco, CA), have recently reported reducing the binding affinity of the T cell receptor complex-binding arm of their respective TCE platforms. However, reducing the binding affinity can result in reduced efficacy and reduced selectivity with respect to the design and functionality of TCEs. For example, it has now been demonstrated that the affinity of the binding domain in such TCEs determines their distribution profile in vivo. Specifically, it is typically observed that the distribution of TCEs is biased toward targets for which they have the highest affinity. Thus, reducing the affinity of the TCE binding domain for the T cell complex typically biases distribution away from T cells, the very cells required for the efficacy of such TCEs. It is for this reason, in part, that TCEs are said to have an "extremely narrow" therapeutic window.

[0023] Furthermore, significant hurdles remain for immunomodulatory therapeutics, particularly in solid tumors. For example, current state-of-the-art approaches include CD3-targeting bispecific drugs, where one domain binds to CD3 and the second domain targets a TAA. However, these have proven problematic in many cases. For example, Middelburg J, et al. Overcoming Challenges for CD3-Bispecific Antibody Therapy in Solid Tumors. Cancers. 2021;13(2):287 summarizes some of these hurdles for multispecific immunomodulatory moieties that engage with T cells in the solid tumor space, including: i. On-target and off-tumor toxicity issues: For example, the authors emphasize that TAAs in solid tumors are often also expressed in healthy organ tissues, which can result in organ dysfunction that can lead to immunopathology and death, as shown in mouse preclinical studies using CD3 bispecific drugs. ii. Availability of effector cells in the tumor microenvironment (TME): For example, conventional CD3+ "naive" T cells reside primarily in the blood and lymphatic systems without further activation by dendritic cells. iii. Quality of tumor infiltrating lymphocytes (TILs), considering that TILs may contain CD3+ Treg cells and / or exhausted CD3+ cells: For example, bispecific drugs targeting CD3 may induce TIL apoptosis by activation-induced cell death, which prevents a potent anti-tumor response.

[0024] Thus, there is a need for improved multispecific immunomodulatory drugs in which at least one binding domain binds to a T cell and at least one second binding domain targets a TAA.

[0025] There is also a need for improved drugs that are specifically designed to target V51+ cells to treat infectious diseases, autoimmune conditions, and cancer. Specifically, there is a need for drugs that can be administered to ameliorate the signs and symptoms of disease by specifically binding to, targeting, activating, enhancing the proliferation and / or cytotoxic activity of, or inhibiting the activation of V51+ cells. Summary of the Invention

[0026] The present invention provides high-affinity anti-TCR delta variable region 1 (anti-V51) antibodies and antibody fragments thereof. The antibodies of the present invention have a favorable functional profile. In particular, unlike prior art anti-V51 antibodies that focus on depleting V51 T cells, the antibodies of the present invention are useful for activating V51 T cells. While the antibodies of the present invention can downregulate the TCR on T cells to which they bind, they do not cause V51 T cell depletion but rather stimulate T cells, making them useful in therapeutic settings that benefit from activation of this T cell compartment. Activation of V51 T cells is evident from TCR downregulation and changes in activation markers, such as CD25, Ki67, the degranulation marker CD107a, NCR (natural cytotoxicity receptor), and / or 4-1BB. Activation of V51 T cells then triggers the release of proinflammatory cytokines, such as INFγ and TNFα, promoting immune licensing. Surprisingly, antibodies with appropriately high affinity for TRDV1 induce increased V51 T cell killing, and unlike antibodies targeting (for example) CD3, high affinity antibodies can be provided without the side effects associated with extensive CD3 activation. As a result, high affinity antibodies can induce potent immunostimulatory effects by tumor-infiltrating lymphocytes (TILs). This can be achieved with minimal exhaustion or killing of V51 cells. Thus, the antibodies of the present invention can be considered agonistic antibodies.

[0027] According to a first aspect of the present invention, a VHCDR3 comprising an amino acid sequence having at least 80% sequence identity to any of SEQ ID NOs: 55 to 78; and / or a VLCDR3 comprising an amino acid sequence having at least 80% sequence identity to any one of SEQ ID NOs: 82 to 105; or a VHCDR3 comprising an amino acid sequence having at least 80% sequence identity to any of SEQ ID NOs: 133 to 143; and / or Provided is an anti-TCRδ variable region 1 (anti-Vδ1) antibody or antigen-binding fragment thereof, which comprises a VLCDR3 comprising an amino acid sequence having at least 80% sequence identity to any of SEQ ID NOs: 147 to 157.

[0028] According to a second aspect of the present invention, there is provided an anti-TCRδ variable region 1 (anti-Vδ1) antibody or antigen-binding fragment thereof, comprising: HCDR1 sequence comprising the sequence of GDSVSSKSX1A (SEQ ID NO: 158); HCDR2 sequence comprising the sequence of SEQ ID NO: 53; an HCDR3 sequence comprising the sequence of X2WX3X4X5X6DX7 (SEQ ID NO: 162), which is not SEQ ID NO: 54; LCDR1 sequence comprising the sequence of SEQ ID NO: 79; An LCDR2 sequence comprising the sequence of SEQ ID NO: 80; and QQX8YX9X 10 X 11 X 12 X 13 T (SEQ ID NO: 166), wherein the LCDR3 sequence is not SEQ ID NO: 81; X1~X 13 each of which is a naturally occurring amino acid, the anti-TCRδ variable region 1 (anti-Vδ1) antibody or antigen-binding fragment thereof; or An anti-TCRδ variable region 1 (anti-Vδ1) antibody or an antigen-binding fragment thereof, HCDR1 sequence comprising the sequence of SEQ ID NO: 130; HCDR2 sequence comprising the sequence of SEQ ID NO: 131; an HCDR3 sequence comprising the sequence of X1X2YX3X4AFDI (SEQ ID NO: 183), which is not SEQ ID NO: 132; LCDR1 sequence comprising the sequence of SEQ ID NO: 144; LCDR2 sequence comprising the sequence of SEQ ID NO: 145; and QQX5X6X7X8LX9T (SEQ ID NO: 186), wherein the LCDR3 sequence is not SEQ ID NO: 146; The anti-TCRδ variable region 1 (anti-Vδ1) antibody or antigen-binding fragment thereof is provided, wherein each of X1 to X9 is a naturally occurring amino acid.

[0029] In a third aspect of the invention, there is provided an anti-TCR delta variable region 1 (anti-V51) antibody or antigen-binding fragment thereof, wherein the anti-V51 antibody or antigen-binding fragment thereof is an affinity matured variant of a parent anti-V51 antibody or antigen-binding fragment thereof, wherein the parent anti-V51 antibody or antigen-binding fragment thereof comprises a VH sequence comprising the amino acid sequence of SEQ ID NO: 1 and a VL sequence comprising the amino acid sequence of SEQ ID NO: 26, or the parent anti-V51 antibody or antigen-binding fragment thereof comprises a VH sequence comprising the amino acid sequence of SEQ ID NO: 106 and a VL sequence comprising the amino acid sequence of SEQ ID NO: 118. Optionally, the first residue of the VH sequence in any affinity matured variant may be Q or E. Optionally, the first two residues of the VL sequence in any affinity matured variant may be absent in any affinity matured variant compared to the original sequence.

[0030] In a fourth aspect of the invention, there is provided an anti-TCR delta variable region 1 (anti-V51) antibody or antigen-binding fragment thereof, wherein the anti-V51 antibody or antigen-binding fragment thereof is an affinity matured variant of a parent anti-V51 antibody or antigen-binding fragment thereof, the parent anti-V51 antibody or antigen-binding fragment thereof comprising: a) a VH comprising the amino acid sequence of SEQ ID NO: 273 and a VL comprising the amino acid sequence of SEQ ID NO: 282; b) a VH comprising the amino acid sequence of SEQ ID NO: 274 and a VL comprising the amino acid sequence of SEQ ID NO: 283; c) a VH comprising the amino acid sequence of SEQ ID NO: 275 and a VL comprising the amino acid sequence of SEQ ID NO: 284; d) a VH comprising the amino acid sequence of SEQ ID NO: 276 and a VL comprising the amino acid sequence of SEQ ID NO: 285; e) a VH comprising the amino acid sequence of SEQ ID NO: 277 and a VL comprising the amino acid sequence of SEQ ID NO: 286; f) a VH comprising the amino acid sequence of SEQ ID NO: 278 and a VL comprising the amino acid sequence of SEQ ID NO: 287; g) a VH comprising the amino acid sequence of SEQ ID NO: 279 and a VL comprising the amino acid sequence of SEQ ID NO: 288; h) a VH comprising the amino acid sequence of SEQ ID NO: 280 and a VL comprising the amino acid sequence of SEQ ID NO: 289; i) a VH comprising the amino acid sequence of SEQ ID NO: 281 and a VL comprising the amino acid sequence of SEQ ID NO: 290; or j) VH comprising the amino acid sequence of SEQ ID NO: 312 and VL comprising the amino acid sequence of SEQ ID NO: 313.

[0031] In a fifth aspect of the present invention, there is provided an anti-TCR delta variable region 1 (anti-V51) antibody or antigen-binding fragment thereof comprising a kappa light chain variable sequence, wherein the residue at position 74 of the kappa light chain variable sequence according to the IMGT numbering system is not serine. In some embodiments, the serine may be substituted with the non-human germline amino acid at position 74. In some embodiments, the substitution may be a non-conservative mutation, for example, substituting a non-polar amino acid for the serine. In some embodiments, the serine may be substituted with a leucine.

[0032] In a sixth aspect of the present invention, there is provided an anti-TCRδ variable region 1 (anti-Vδ1) antibody or an antigen-binding fragment thereof that specifically binds to the variable δ1 (Vδ1) chain of the γδ T cell receptor (TCR) and competes with an antibody or antigen-binding fragment thereof of any of the first to fifth aspects of the present invention for binding to the variable δ1 (Vδ1) chain of the γδ T cell receptor (TCR).

[0033] A seventh aspect of the present invention provides a polynucleotide sequence encoding an anti-Vδ1 antibody or antigen-binding fragment thereof of the present invention, for example, a polynucleotide sequence encoding an anti-Vδ1 antibody or antigen-binding fragment thereof comprising a sequence having at least 70% sequence identity with SEQ ID NOs: 199-222, 224-247, 249-259, or 261-271.

[0034] In an eighth aspect of the present invention, there is provided an expression vector comprising a polynucleotide sequence of the present invention. Host cells comprising the polynucleotide sequence of the present invention or the expression vector of the present invention are also provided. Also provided is a method for producing any of the antibodies or antigen-binding fragments thereof of the present invention, comprising culturing a host cell of the present invention in a cell culture medium.

[0035] In a further aspect of the present invention, there is provided a composition comprising an antibody or antibody-binding fragment thereof of the present invention. There is also provided a pharmaceutical composition comprising an antibody or antibody-binding fragment thereof of the present invention and a pharmaceutically acceptable diluent or carrier. The composition and pharmaceutical composition may optionally further comprise one or more additional therapeutically active agents.

[0036] In a further aspect of the invention, there is provided a kit comprising an anti-V51 antibody or antibody-binding fragment of the invention, or a pharmaceutical composition of the invention, and optionally including instructions for use and / or an additional therapeutically active agent.

[0037] In a further aspect of the present invention, there is provided a method for treating a disease or disorder in a subject, the method comprising administering to the subject an anti-V51 antibody or antibody-binding fragment of the present invention, or a pharmaceutical composition of the present invention. There is also provided a method for regulating an immune response in a subject, the method comprising administering to the subject an anti-V51 antibody or antibody-binding fragment of the present invention, or a pharmaceutical composition of the present invention. The antibody may be administered to the subject in a therapeutically effective amount.

[0038] In yet another aspect of the present invention, there is provided a method of mutating an antibody or antigen-binding fragment thereof, the method comprising providing an antibody comprising a kappa light chain having a serine at position 74 according to the IMGT numbering system, and substituting (e.g., mutating) the serine with a different amino acid. In some embodiments, the serine may be substituted with the non-human germline amino acid at position 74. In some embodiments, the substitution may be a non-conservative mutation, e.g., substituting a non-polar amino acid for the serine. In some embodiments, the serine may be substituted with a leucine.

[0039] In a further aspect of the invention there is provided a method for preparing an anti-TCR delta variable region 1 (anti-V51) antibody variant or antigen-binding fragment thereof, comprising the steps of: a) a VH comprising the amino acid sequence of SEQ ID NO: 1 and a VL comprising the amino acid sequence of SEQ ID NO: 26; b) a VH comprising the amino acid sequence of SEQ ID NO: 106 and a VL comprising the amino acid sequence of SEQ ID NO: 118; c) a VH comprising the amino acid sequence of SEQ ID NO: 273 and a VL comprising the amino acid sequence of SEQ ID NO: 282; d) a VH comprising the amino acid sequence of SEQ ID NO: 274 and a VL comprising the amino acid sequence of SEQ ID NO: 283; e) a VH comprising the amino acid sequence of SEQ ID NO: 275 and a VL comprising the amino acid sequence of SEQ ID NO: 284; f) a VH comprising the amino acid sequence of SEQ ID NO: 276 and a VL comprising the amino acid sequence of SEQ ID NO: 285; g) a VH comprising the amino acid sequence of SEQ ID NO: 277 and a VL comprising the amino acid sequence of SEQ ID NO: 286; h) a VH comprising the amino acid sequence of SEQ ID NO: 278 and a VL comprising the amino acid sequence of SEQ ID NO: 287; i) a VH comprising the amino acid sequence of SEQ ID NO: 279 and a VL comprising the amino acid sequence of SEQ ID NO: 288; j) a VH comprising the amino acid sequence of SEQ ID NO: 280 and a VL comprising the amino acid sequence of SEQ ID NO: 289; k) a VH comprising the amino acid sequence of SEQ ID NO: 281 and a VL comprising the amino acid sequence of SEQ ID NO: 290; or l) providing a parent antibody comprising a VH comprising the amino acid sequence of SEQ ID NO: 312 and a VL comprising the amino acid sequence of SEQ ID NO: 313; and subjecting the antibody to affinity maturation, wherein the generated antibody has a stronger and higher affinity for the variable δ1 (Vδ1) chain of the γδ T-cell receptor (TCR) compared to the parent antibody.

[0040] In a further aspect of the invention, there is provided a method for preparing a pharmaceutical composition, the method comprising providing an antibody prepared according to the method for preparing an anti-TCR delta variable region 1 (anti-V51) antibody variant or antigen-binding fragment of the invention, and co-forming the antibody with at least one or more pharmaceutically acceptable diluents or carriers.

[0041] In yet another aspect, the present invention provides an anti-TCR delta variable region 1 (anti-V51) antibody or antigen-binding fragment thereof of the present invention for use in medicine, a pharmaceutical composition of the present invention, or a kit of the present invention. Also provided is the use of an anti-TCR delta variable region 1 (anti-V51) antibody or antigen-binding fragment thereof of the present invention in the manufacture of a medicament. [Brief explanation of the drawings]

[0042] [Figure 1] ELISA detection of directly coated antigens with anti-Vδ1 Ab (REA173, Miltenyi Biotec). Detection was only observed for antigens containing the Vδ1 domain. The leucine zipper (LZ) format appeared to be more potent than the Fc format, consistent with cell-based flow competition assays (data not shown). [Figure 2] Polyclonal phage DELFIA data for DV1 selection. (A) Heterodimer selection: heterodimeric LZ TCR format in rounds 1 and 2, deselection of heterodimeric LZ TCR in both rounds. (B) Homodimer selection: Round 1 was performed using homodimeric Fc-fusion TCR and deselection of human IgG1 Fc, followed by round 2 against heterodimeric LZ TCR and deselection of heterodimeric LZ TCR. Each graph contains two bars for each target to represent selection from different libraries. [Figure 3] IgG capture: Left) Sensorgram of the interaction of anti-L1 IgG with L1, Right) Steady-state fit where available. All experiments were performed on a MASS-2 instrument at room temperature. The steady-state fit follows Langmuir 1:1 binding. [Figure 4]Results of TCR downregulation assays (using THP-1 preloaded antibodies) for clones 1245_P01_E07, 1252_P01_C08, 1245_P02_G04, 1245_P01_B07 and 1251_P02_C05 (A), or clones 1139_P01_E04, 1245_P02_F07, 1245_P01_G06 1245_P01_G09, 1138_P01_B09, 1251_P02_G10 and 1252_P01_C08 (B). [Figure 5] Results of T cell degranulation assay for clones 1245_P01_E07, 1252_P01_C08, 1245_P02_G04, 1245_P01_B07 and 1251_P02_C05 (A), or clones 1139_P01_E04, 1245_P02_F07, 1245_P01_G06, 1245_P01_G09, 1138_P01_B09, and 1251_P02_G10 (B). [Figure 6] Results of injury assay (THP-1 flow-based assay) for clones 1245_P01_E07, 1252_P01_C08, 1245_P02_G04, 1245_P01_B07, and 1251_P02_C05 (A), or clones 1139_P01_E04, 1245_P02_F07, 1245_P01_G06, 1245_P01_G09, 1138_P01_B09, and 1251_P02_G10 (B). [Figure 7] Total cell counts in experiment 1 of Example 10. Samples were cultured with various concentrations of anti-V51 antibodies described herein and compared to samples cultured with a comparator antibody or control. Graphs show total cell counts at (A) day 7, (B) day 14, and (C) day 18. [Figure 8] Analysis of V51 T cells in experiment 1 of Example 10. Graphs show (A) percentage of V51 T cells, (B) number of V51 T cells, and (C) V51 fold change in samples on day 18. [Figure 9A]Total cell counts in experiment 2 of Example 10. Samples were cultured with various concentrations of anti-V51 antibodies described herein and compared to samples cultured with a comparator antibody or control. Graphs show total cell counts at (A) day 7, (B) day 11, (C) day 14, and (D) day 17. [Figure 9B] Total cell counts in experiment 2 of Example 10. Samples were cultured with various concentrations of anti-V51 antibodies described herein and compared to samples cultured with a comparator antibody or control. Graphs show total cell counts at (A) day 7, (B) day 11, (C) day 14, and (D) day 17. [Figure 9C] Total cell counts in experiment 2 of Example 10. Samples were cultured with various concentrations of anti-V51 antibodies described herein and compared to samples cultured with a comparator antibody or control. Graphs show total cell counts at (A) day 7, (B) day 11, (C) day 14, and (D) day 17. [Figure 9D] Total cell counts in experiment 2 of Example 10. Samples were cultured with various concentrations of anti-V51 antibodies described herein and compared to samples cultured with a comparator antibody or control. Graphs show total cell counts at (A) day 7, (B) day 11, (C) day 14, and (D) day 17. [Figure 10] Analysis of V51 T cells in experiment 2 of Example 10. Graphs show (A) percentage of V51 T cells, (B) number of V51 T cells, and (C) V51 fold change in samples on day 17. [Figure 11] Cell composition analysis. The cell types present in the samples (including non-V51 cells) were determined on day 17 of experiment 2. Cells were harvested and analyzed by flow cytometry for surface expression of V51, V52 and αβ TCR. Percentage values ​​are also presented in Table 12. [Figure 12] SYTOX flow injury assay results. Cell functionality was tested using the SYTOX flow injury assay, and results are presented for (A) day 14 of experiment 1, using cells at a 10:1 effector-to-target (E:T) ratio, and (B) day 17 (post-freeze-thaw) of experiment 2, using cells at 1:1 and 10:1 E:T ratios. [Figure 13] Total cell number after freeze-thaw. The graph shows the total cell number after 7 days of culturing the cells after freeze-thawing for cultures that were contacted with B07, C08, E07, G04, or OKT-3 antibodies before freezing. [Figure 14] Monitoring cell expansion. The total cell number of cells cultured after freezing and thawing was monitored up to 42 days. [Figure 15] Binding equivalence studies of engineered anti-Vδ1 antibodies [Figure 16] Anti-Vδ1 antibody binding equivalence studies against the human germline Vδ1 antigen and its polymorphic variants. [Figure 17] Anti-V51 antibodies conferred increased cytokine secretion levels in V51+ cells. Tissue-derived γδ T cells were incubated with the indicated antibodies. (A) Observed levels of TNF-alpha. (B) Observed levels of IFN-gamma. [Figure 18] Anti-Vδ1 antibodies conferred increased Vδ1+ cell granzyme B levels / activity. Cancer cells were co-cultured with tissue-derived γδ T cells at a constant T:E ratio of 1:20 and the indicated antibodies for 1 hour. Results show the amount of granzyme B detected in cancer cells at the end of co-culture. [Figure 19] Anti-V51 antibodies conferred immune cell modulation and proliferation in human tissues. Human skin punch biopsies (from five different donors) were incubated with the indicated antibodies in culture for 21 days. (A) Number of viable pan-γ5 cells. (B) Number of viable V51 cells. (C) Percentage of viable double-positive V51 CD25 cells. [Figure 20] Anti-Vδ1 antibodies conferred modulation and proliferation of tumor-infiltrating lymphocytes (TILs) in human tumors. Study on renal cell carcinoma (RCC) + / - subjects. (A) Fold increase in TIL Vδ1+ cells. (B) Total number of TIL Vδ1+ cells. (C) Example of gating strategy. (D) Comparison of cell surface phenotypic profile of TIL Vδ1+ cells. (E) Analysis of TIL Vδ1-negative gated fraction. [Figure 21A]Anti-V51 antibodies conferred enhanced V51+-mediated cytotoxicity and disease-cell-specific cytotoxicity. Cytotoxicity / potency assay in a model system involving triple culture of V51+ effector cells, THP-1 monocytic cancer cells, and non-diseased healthy primary monocytes. (A) Quantification of the number of THP-1 and monocytic cells in triple coculture with γδ T cells in the presence of anti-V51 mAb or control. (B) Bar graph representation highlighting the window between specific killing of diseased cells and non-diseased healthy cells: left bar graph; fold increase in killing of diseased cells (THP-1) versus non-diseased cells (primary human monocytes); right bar graph; same data but expressed as percent enhanced killing relative to control. (C) Tabular results summarizing the percent enhancement of V51+ effector cytotoxicity of THP-1 target cells ± mAb. (D) Tabular results of EC50 values ​​calculated from figure (A), expressed as the number of γδ T cells required to confer 50% THP-1 cytotoxicity. [Figure 21B] Anti-V51 antibodies conferred enhanced V51+-mediated cytotoxicity and disease-cell-specific cytotoxicity. Cytotoxicity / potency assay in a model system involving triple culture of V51+ effector cells, THP-1 monocytic cancer cells, and non-diseased healthy primary monocytes. (A) Quantification of the number of THP-1 and monocytic cells in triple coculture with γδ T cells in the presence of anti-V51 mAb or control. (B) Bar graph representation highlighting the window between specific killing of diseased cells and non-diseased healthy cells: left bar graph; fold increase in killing of diseased cells (THP-1) versus non-diseased cells (primary human monocytes); right bar graph; same data but expressed as percent enhanced killing relative to control. (C) Tabular results summarizing the percent enhancement of V51+ effector cytotoxicity of THP-1 target cells ± mAb. (D) Tabular results of EC50 values ​​calculated from figure (A), expressed as the number of γδ T cells required to confer 50% THP-1 cytotoxicity. [Figure 21C]Anti-V51 antibodies conferred enhanced V51+-mediated cytotoxicity and disease-cell-specific cytotoxicity. Cytotoxicity / potency assay in a model system involving triple culture of V51+ effector cells, THP-1 monocytic cancer cells, and non-diseased healthy primary monocytes. (A) Quantification of the number of THP-1 and monocytic cells in triple coculture with γδ T cells in the presence of anti-V51 mAb or control. (B) Bar graph representation highlighting the window between specific killing of diseased cells and non-diseased healthy cells: left bar graph; fold increase in killing of diseased cells (THP-1) versus non-diseased cells (primary human monocytes); right bar graph; same data but expressed as percent enhanced killing relative to control. (C) Tabular results summarizing the percent enhancement of V51+ effector cytotoxicity of THP-1 target cells ± mAb. (D) Tabular results of EC50 values ​​calculated from figure (A), expressed as the number of γδ T cells required to confer 50% THP-1 cytotoxicity. [Figure 21D] Anti-V51 antibodies conferred enhanced V51+-mediated cytotoxicity and disease-cell-specific cytotoxicity. Cytotoxicity / potency assay in a model system involving triple culture of V51+ effector cells, THP-1 monocytic cancer cells, and non-diseased healthy primary monocytes. (A) Quantification of the number of THP-1 and monocytic cells in triple coculture with γδ T cells in the presence of anti-V51 mAb or control. (B) Bar graph representation highlighting the window between specific killing of diseased cells and non-diseased healthy cells: left bar graph; fold increase in killing of diseased cells (THP-1) versus non-diseased cells (primary human monocytes); right bar graph; same data but expressed as percent enhanced killing relative to control. (C) Tabular results summarizing the percent enhancement of V51+ effector cytotoxicity of THP-1 target cells ± mAb. (D) Tabular results of EC50 values ​​calculated from figure (A), expressed as the number of γδ T cells required to confer 50% THP-1 cytotoxicity. [Figure 22A]Multispecific antibodies conferred enhanced V51+ effector cell-mediated cytotoxicity. Targeting tissue-centric disease-associated antigens: (A-D) Example of co-culture of V51+ effector cells with A-431 cancer cells with or without (+ / -) a multispecific antibody containing an anti-V51 x anti-TAA(EGFR) bispecific binding site, in which an anti-V51 VL+VH binding domain (against the first target) is combined with the CH1-CH2-CH3 domains of an anti-EGFR binding site (against the second target). (E-H) Example of co-culture of V51+ effector cells with A-431 cancer cells with or without a multispecific antibody containing an anti-V51 x anti-TAA(EGFR) bispecific binding site, in which the anti-V51 binding domain (against the first target) comprises a full-length antibody (VH-CH1-CH2-CH3 / VL-CL) and is then combined with an anti-EGFR cetuximab-derived scFv binding site (against the second target). (I-J) An alternative approach to expressing the data: the percentage improvement that the multispecific antibody confers on V51+ effector cytotoxicity against EGFR+ cells relative to the constituent moieties. [Figure 22B] Multispecific antibodies conferred enhanced V51+ effector cell-mediated cytotoxicity. Targeting tissue-centric disease-associated antigens: (A-D) Example of co-culture of V51+ effector cells with A-431 cancer cells with or without (+ / -) a multispecific antibody containing an anti-V51 x anti-TAA(EGFR) bispecific binding site, in which an anti-V51 VL+VH binding domain (against the first target) is combined with the CH1-CH2-CH3 domains of an anti-EGFR binding site (against the second target). (E-H) Example of co-culture of V51+ effector cells with A-431 cancer cells with or without a multispecific antibody containing an anti-V51 x anti-TAA(EGFR) bispecific binding site, in which the anti-V51 binding domain (against the first target) comprises a full-length antibody (VH-CH1-CH2-CH3 / VL-CL) and is then combined with an anti-EGFR cetuximab-derived scFv binding site (against the second target). (I-J) An alternative approach to expressing the data: the percentage improvement that the multispecific antibody confers on V51+ effector cytotoxicity against EGFR+ cells relative to the constituent moieties. [Figure 22C]Multispecific antibodies conferred enhanced V51+ effector cell-mediated cytotoxicity. Targeting tissue-centric disease-associated antigens: (A-D) Example of co-culture of V51+ effector cells with A-431 cancer cells with or without (+ / -) a multispecific antibody containing an anti-V51 x anti-TAA(EGFR) bispecific binding site, in which an anti-V51 VL+VH binding domain (against the first target) is combined with the CH1-CH2-CH3 domains of an anti-EGFR binding site (against the second target). (E-H) Example of co-culture of V51+ effector cells with A-431 cancer cells with or without a multispecific antibody containing an anti-V51 x anti-TAA(EGFR) bispecific binding site, in which the anti-V51 binding domain (against the first target) comprises a full-length antibody (VH-CH1-CH2-CH3 / VL-CL) and is then combined with an anti-EGFR cetuximab-derived scFv binding site (against the second target). (I-J) An alternative approach to expressing the data: the percentage improvement that the multispecific antibody confers on V51+ effector cytotoxicity against EGFR+ cells relative to the constituent moieties. [Figure 22D] Multispecific antibodies conferred enhanced V51+ effector cell-mediated cytotoxicity. Targeting tissue-centric disease-associated antigens: (A-D) Example of co-culture of V51+ effector cells with A-431 cancer cells with or without (+ / -) a multispecific antibody containing an anti-V51 x anti-TAA(EGFR) bispecific binding site, in which an anti-V51 VL+VH binding domain (against the first target) is combined with the CH1-CH2-CH3 domains of an anti-EGFR binding site (against the second target). (E-H) Example of co-culture of V51+ effector cells with A-431 cancer cells with or without a multispecific antibody containing an anti-V51 x anti-TAA(EGFR) bispecific binding site, in which the anti-V51 binding domain (against the first target) comprises a full-length antibody (VH-CH1-CH2-CH3 / VL-CL) and is then combined with an anti-EGFR cetuximab-derived scFv binding site (against the second target). (I-J) An alternative approach to expressing the data: the percentage improvement that the multispecific antibody confers on V51+ effector cytotoxicity against EGFR+ cells relative to the constituent moieties. [Figure 22E]Multispecific antibodies conferred enhanced V51+ effector cell-mediated cytotoxicity. Targeting tissue-centric disease-associated antigens: (A-D) Example of co-culture of V51+ effector cells with A-431 cancer cells with or without (+ / -) a multispecific antibody containing an anti-V51 x anti-TAA(EGFR) bispecific binding site, in which an anti-V51 VL+VH binding domain (against the first target) is combined with the CH1-CH2-CH3 domains of an anti-EGFR binding site (against the second target). (E-H) Example of co-culture of V51+ effector cells with A-431 cancer cells with or without a multispecific antibody containing an anti-V51 x anti-TAA(EGFR) bispecific binding site, in which the anti-V51 binding domain (against the first target) comprises a full-length antibody (VH-CH1-CH2-CH3 / VL-CL) and is then combined with an anti-EGFR cetuximab-derived scFv binding site (against the second target). (I-J) An alternative approach to expressing the data: the percentage improvement that the multispecific antibody confers on V51+ effector cytotoxicity against EGFR+ cells relative to the constituent moieties. [Figure 22F] Multispecific antibodies conferred enhanced V51+ effector cell-mediated cytotoxicity. Targeting tissue-centric disease-associated antigens: (A-D) Example of co-culture of V51+ effector cells with A-431 cancer cells with or without (+ / -) a multispecific antibody containing an anti-V51 x anti-TAA(EGFR) bispecific binding site, in which an anti-V51 VL+VH binding domain (against the first target) is combined with the CH1-CH2-CH3 domains of an anti-EGFR binding site (against the second target). (E-H) Example of co-culture of V51+ effector cells with A-431 cancer cells with or without a multispecific antibody containing an anti-V51 x anti-TAA(EGFR) bispecific binding site, in which the anti-V51 binding domain (against the first target) comprises a full-length antibody (VH-CH1-CH2-CH3 / VL-CL) and is then combined with an anti-EGFR cetuximab-derived scFv binding site (against the second target). (I-J) An alternative approach to expressing the data: the percentage improvement that the multispecific antibody confers on V51+ effector cytotoxicity against EGFR+ cells relative to the constituent moieties. [Figure 22G]Multispecific antibodies conferred enhanced V51+ effector cell-mediated cytotoxicity. Targeting tissue-centric disease-associated antigens: (A-D) Example of co-culture of V51+ effector cells with A-431 cancer cells with or without (+ / -) a multispecific antibody containing an anti-V51 x anti-TAA(EGFR) bispecific binding site, in which an anti-V51 VL+VH binding domain (against the first target) is combined with the CH1-CH2-CH3 domains of an anti-EGFR binding site (against the second target). (E-H) Example of co-culture of V51+ effector cells with A-431 cancer cells with or without a multispecific antibody containing an anti-V51 x anti-TAA(EGFR) bispecific binding site, in which the anti-V51 binding domain (against the first target) comprises a full-length antibody (VH-CH1-CH2-CH3 / VL-CL) and is then combined with an anti-EGFR cetuximab-derived scFv binding site (against the second target). (I-J) An alternative approach to expressing the data: the percentage improvement that the multispecific antibody confers on V51+ effector cytotoxicity against EGFR+ cells relative to the constituent moieties. [Figure 22H] Multispecific antibodies conferred enhanced V51+ effector cell-mediated cytotoxicity. Targeting tissue-centric disease-associated antigens: (A-D) Example of co-culture of V51+ effector cells with A-431 cancer cells with or without (+ / -) a multispecific antibody containing an anti-V51 x anti-TAA(EGFR) bispecific binding site, in which an anti-V51 VL+VH binding domain (against the first target) is combined with the CH1-CH2-CH3 domains of an anti-EGFR binding site (against the second target). (E-H) Example of co-culture of V51+ effector cells with A-431 cancer cells with or without a multispecific antibody containing an anti-V51 x anti-TAA(EGFR) bispecific binding site, in which the anti-V51 binding domain (against the first target) comprises a full-length antibody (VH-CH1-CH2-CH3 / VL-CL) and is then combined with an anti-EGFR cetuximab-derived scFv binding site (against the second target). (I-J) An alternative approach to expressing the data: the percentage improvement that the multispecific antibody confers on V51+ effector cytotoxicity against EGFR+ cells relative to the constituent moieties. [Figure 22I]Multispecific antibodies conferred enhanced V51+ effector cell-mediated cytotoxicity. Targeting tissue-centric disease-associated antigens: (A-D) Example of co-culture of V51+ effector cells with A-431 cancer cells with or without (+ / -) a multispecific antibody containing an anti-V51 x anti-TAA(EGFR) bispecific binding site, in which an anti-V51 VL+VH binding domain (against the first target) is combined with the CH1-CH2-CH3 domains of an anti-EGFR binding site (against the second target). (E-H) Example of co-culture of V51+ effector cells with A-431 cancer cells with or without a multispecific antibody containing an anti-V51 x anti-TAA(EGFR) bispecific binding site, in which the anti-V51 binding domain (against the first target) comprises a full-length antibody (VH-CH1-CH2-CH3 / VL-CL) and is then combined with an anti-EGFR cetuximab-derived scFv binding site (against the second target). (I-J) An alternative approach to expressing the data: the percentage improvement that the multispecific antibody confers on V51+ effector cytotoxicity against EGFR+ cells relative to the constituent moieties. [Figure 22J] Multispecific antibodies conferred enhanced V51+ effector cell-mediated cytotoxicity. Targeting tissue-centric disease-associated antigens: (A-D) Example of co-culture of V51+ effector cells with A-431 cancer cells with or without (+ / -) a multispecific antibody containing an anti-V51 x anti-TAA(EGFR) bispecific binding site, in which an anti-V51 VL+VH binding domain (against the first target) is combined with the CH1-CH2-CH3 domains of an anti-EGFR binding site (against the second target). (E-H) Example of co-culture of V51+ effector cells with A-431 cancer cells with or without a multispecific antibody containing an anti-V51 x anti-TAA(EGFR) bispecific binding site, in which the anti-V51 binding domain (against the first target) comprises a full-length antibody (VH-CH1-CH2-CH3 / VL-CL) and is then combined with an anti-EGFR cetuximab-derived scFv binding site (against the second target). (I-J) An alternative approach to expressing the data: the percentage improvement that the multispecific antibody confers on V51+ effector cytotoxicity against EGFR+ cells relative to the constituent moieties. [Figure 23A]Multispecific antibodies conferred enhanced V51+-mediated cytotoxicity and disease cell-specific cytotoxicity. Targeting hematopoietic disease-associated antigens. (A) E:T ratio required to induce 50% Raji cytotoxicity. (B) Percentage of improvement with addition of V51-CD19 multispecific antibodies. [Figure 23B] Multispecific antibodies conferred enhanced V51+-mediated cytotoxicity and disease cell-specific cytotoxicity. Targeting hematopoietic disease-associated antigens. (A) E:T ratio required to induce 50% Raji cytotoxicity. (B) Percentage of improvement with addition of V51-CD19 multispecific antibodies. [Figure 24A] Phage selection rounds. (A) Phage selection rounds 1-3 for the ADT1-7 library. (B) Phage selection rounds 1-3 for the ADT1-4 library. (C) Phage selection rounds 1-3 for the ADT1-4 library using a selection strategy to isolate cynomolgus monkey cross-reactive binders. [Figure 24B] Phage selection rounds. (A) Phage selection rounds 1-3 for the ADT1-7 library. (B) Phage selection rounds 1-3 for the ADT1-4 library. (C) Phage selection rounds 1-3 for the ADT1-4 library using a selection strategy to isolate cynomolgus monkey cross-reactive binders. [Figure 24C] Phage selection rounds. (A) Phage selection rounds 1-3 for the ADT1-7 library. (B) Phage selection rounds 1-3 for the ADT1-4 library. (C) Phage selection rounds 1-3 for the ADT1-4 library using a selection strategy to isolate cynomolgus monkey cross-reactive binders. [Figure 25A] Schematic diagram of selection of mature antibodies by mammalian display. (A) Schematic diagram of flow sorting of ADT1-7 library. (B) Schematic diagram of flow sorting of ADT1-4 library 1 (human). (C) Schematic diagram of flow sorting of ADT1-4 library 2 (cynomolgus monkey). [Figure 25B]Schematic diagram of selection of mature antibodies by mammalian display. (A) Schematic diagram of flow sorting of ADT1-7 library. (B) Schematic diagram of flow sorting of ADT1-4 library 1 (human). (C) Schematic diagram of flow sorting of ADT1-4 library 2 (cynomolgus monkey). [Figure 25C] Schematic diagram of selection of mature antibodies by mammalian display. (A) Schematic diagram of flow sorting of ADT1-7 library. (B) Schematic diagram of flow sorting of ADT1-4 library 1 (human). (C) Schematic diagram of flow sorting of ADT1-4 library 2 (cynomolgus monkey). [Figure 26A]Effect of the kappa chain S74L change on affinity. (A) ADT1-4 lineage mammalian display output: Human dissociation off-rate (SPR) versus human antigen binding (Delfia ELISA, 0.4 nM human antigen) using LC 74S (open circles) or 74L (filled circles). The results highlight the good match between the affinity improvement by SPR and the affinity improvement by antigen binding by Dellfia ELISA. These results also highlight the improved binding conferred by the variable domain S74L modification. (B) ADT1-4 lineage mammalian display output: Cynomolgus monkey dissociation off-rate (SPR) versus Cynomolgus monkey antigen binding (Delfia ELISA, 10 nM Cyno antigen) using LC 74S (open circles) or 74L (filled circles). (C) ADT1-4 lineage mammalian display output: correlation between human antigen dissociation off-rate (SPR) improvement versus cynomolgus monkey antigen dissociation off-rate (SPR) + LC 74S (open circles) or 74L (filled circles) use. (D) Further confirmation of the effect of S74 vs. L74 on ADT1-4 lineage affinity. The starting serine at position 74 of the kappa chain of the low-affinity parent ADT1-4 was mutated to leucine to create the kappa chain of SEQ ID NO: 504. This modified light chain was paired with the starting ADT1-4 VH (SEQ ID NO: 1) to create the new molecule "ADT1-4(S74L)" as shown. The starting leucine at position 74 of the kappa chain of the high-affinity ADT1-4-2 was changed back to serine to create the kappa chain of SEQ ID NO: 505. This was paired with the ADT1-4-2 VH (SEQ ID NO: 15) to create the new molecule "ADT1-4-2(L74S)." The affinity of these molecules (to the starting molecules ADT1-4 and ADT1-4-2, respectively) was determined by SPR analysis using a Reichert 4SPR instrument (Reichert Technologies). The antibody (1.5 μg / mL) was coated onto a Planar Protein A Sensor Chip (Reichert Technologies), resulting in a baseline increase of approximately 500 μRIU.Recombinant human or cynomolgus V51 heterodimers were flowed over the cells at concentrations of 100 nM, 50 nM, 25 nM, 12.5 nM, and 6.25 nM using the following parameters: association 180 s, dissociation 480 s, flow rate 25 μL / min, running buffer PBS + 0.05% Tween 20. All experiments were performed at room temperature: (Di) Results of the resulting SPR traces showing the affinity of the antibodies shown for human and cynomolgus V51 antigens. (Dii) Summary of the results tabulated. [Figure 26B]Effect of the kappa chain S74L change on affinity. (A) ADT1-4 lineage mammalian display output: Human dissociation off-rate (SPR) versus human antigen binding (Delfia ELISA, 0.4 nM human antigen) using LC 74S (open circles) or 74L (filled circles). The results highlight the good match between the affinity improvement by SPR and the affinity improvement by antigen binding by Dellfia ELISA. These results also highlight the improved binding conferred by the variable domain S74L modification. (B) ADT1-4 lineage mammalian display output: Cynomolgus monkey dissociation off-rate (SPR) versus Cynomolgus monkey antigen binding (Delfia ELISA, 10 nM Cyno antigen) using LC 74S (open circles) or 74L (filled circles). (C) ADT1-4 lineage mammalian display output: correlation between human antigen dissociation off-rate (SPR) improvement versus cynomolgus monkey antigen dissociation off-rate (SPR) + LC 74S (open circles) or 74L (filled circles) use. (D) Further confirmation of the effect of S74 vs. L74 on ADT1-4 lineage affinity. The starting serine at position 74 of the kappa chain of the low-affinity parent ADT1-4 was mutated to leucine to create the kappa chain of SEQ ID NO: 504. This modified light chain was paired with the starting ADT1-4 VH (SEQ ID NO: 1) to create the new molecule "ADT1-4(S74L)" as shown. The starting leucine at position 74 of the kappa chain of the high-affinity ADT1-4-2 was changed back to serine to create the kappa chain of SEQ ID NO: 505. This was paired with the ADT1-4-2 VH (SEQ ID NO: 15) to create the new molecule "ADT1-4-2(L74S)." The affinity of these molecules (to the starting molecules ADT1-4 and ADT1-4-2, respectively) was determined by SPR analysis using a Reichert 4SPR instrument (Reichert Technologies). The antibody (1.5 μg / mL) was coated onto a Planar Protein A Sensor Chip (Reichert Technologies), resulting in a baseline increase of approximately 500 μRIU.Recombinant human or cynomolgus V51 heterodimers were flowed over the cells at concentrations of 100 nM, 50 nM, 25 nM, 12.5 nM, and 6.25 nM using the following parameters: association 180 s, dissociation 480 s, flow rate 25 μL / min, running buffer PBS + 0.05% Tween 20. All experiments were performed at room temperature: (Di) Results of the resulting SPR traces showing the affinity of the antibodies shown for human and cynomolgus V51 antigens. (Dii) Summary of the results tabulated. [Figure 26C]Effect of the kappa chain S74L change on affinity. (A) ADT1-4 lineage mammalian display output: Human dissociation off-rate (SPR) versus human antigen binding (Delfia ELISA, 0.4 nM human antigen) using LC 74S (open circles) or 74L (filled circles). The results highlight the good match between the affinity improvement by SPR and the affinity improvement by antigen binding by Dellfia ELISA. These results also highlight the improved binding conferred by the variable domain S74L modification. (B) ADT1-4 lineage mammalian display output: Cynomolgus monkey dissociation off-rate (SPR) versus Cynomolgus monkey antigen binding (Delfia ELISA, 10 nM Cyno antigen) using LC 74S (open circles) or 74L (filled circles). (C) ADT1-4 lineage mammalian display output: correlation between human antigen dissociation off-rate (SPR) improvement versus cynomolgus monkey antigen dissociation off-rate (SPR) + LC 74S (open circles) or 74L (filled circles) use. (D) Further confirmation of the effect of S74 vs. L74 on ADT1-4 lineage affinity. The starting serine at position 74 of the kappa chain of the low-affinity parent ADT1-4 was mutated to leucine to create the kappa chain of SEQ ID NO: 504. This modified light chain was paired with the starting ADT1-4 VH (SEQ ID NO: 1) to create the new molecule "ADT1-4(S74L)" as shown. The starting leucine at position 74 of the kappa chain of the high-affinity ADT1-4-2 was changed back to serine to create the kappa chain of SEQ ID NO: 505. This was paired with the ADT1-4-2 VH (SEQ ID NO: 15) to create the new molecule "ADT1-4-2(L74S)." The affinity of these molecules (to the starting molecules ADT1-4 and ADT1-4-2, respectively) was determined by SPR analysis using a Reichert 4SPR instrument (Reichert Technologies). The antibody (1.5 μg / mL) was coated onto a Planar Protein A Sensor Chip (Reichert Technologies), resulting in a baseline increase of approximately 500 μRIU.Recombinant human or cynomolgus V51 heterodimers were flowed over the cells at concentrations of 100 nM, 50 nM, 25 nM, 12.5 nM, and 6.25 nM using the following parameters: association 180 s, dissociation 480 s, flow rate 25 μL / min, running buffer PBS + 0.05% Tween 20. All experiments were performed at room temperature: (Di) Results of the resulting SPR traces showing the affinity of the antibodies shown for human and cynomolgus V51 antigens. (Dii) Summary of the results tabulated. [Figure 26D]Effect of the kappa chain S74L change on affinity. (A) ADT1-4 lineage mammalian display output: Human dissociation off-rate (SPR) versus human antigen binding (Delfia ELISA, 0.4 nM human antigen) using LC 74S (open circles) or 74L (filled circles). The results highlight the good match between the affinity improvement by SPR and the affinity improvement by antigen binding by Dellfia ELISA. These results also highlight the improved binding conferred by the variable domain S74L modification. (B) ADT1-4 lineage mammalian display output: Cynomolgus monkey dissociation off-rate (SPR) versus Cynomolgus monkey antigen binding (Delfia ELISA, 10 nM Cyno antigen) using LC 74S (open circles) or 74L (filled circles). (C) ADT1-4 lineage mammalian display output: correlation between human antigen dissociation off-rate (SPR) improvement versus cynomolgus monkey antigen dissociation off-rate (SPR) + LC 74S (open circles) or 74L (filled circles) use. (D) Further confirmation of the effect of S74 vs. L74 on ADT1-4 lineage affinity. The starting serine at position 74 of the kappa chain of the low-affinity parent ADT1-4 was mutated to leucine to create the kappa chain of SEQ ID NO: 504. This modified light chain was paired with the starting ADT1-4 VH (SEQ ID NO: 1) to create the new molecule "ADT1-4(S74L)" as shown. The starting leucine at position 74 of the kappa chain of the high-affinity ADT1-4-2 was changed back to serine to create the kappa chain of SEQ ID NO: 505. This was paired with the ADT1-4-2 VH (SEQ ID NO: 15) to create the new molecule "ADT1-4-2(L74S)." The affinity of these molecules (to the starting molecules ADT1-4 and ADT1-4-2, respectively) was determined by SPR analysis using a Reichert 4SPR instrument (Reichert Technologies). The antibody (1.5 μg / mL) was coated onto a Planar Protein A Sensor Chip (Reichert Technologies), resulting in a baseline increase of approximately 500 μRIU.Recombinant human or cynomolgus V51 heterodimers were flowed over the cells at concentrations of 100 nM, 50 nM, 25 nM, 12.5 nM, and 6.25 nM using the following parameters: association 180 s, dissociation 480 s, flow rate 25 μL / min, running buffer PBS + 0.05% Tween 20. All experiments were performed at room temperature: (Di) Results of the resulting SPR traces showing the affinity of the antibodies shown for human and cynomolgus V51 antigens. (Dii) Summary of the results tabulated. [Figure 27A] CDR3 Usage and Cross-Sharing. (A) Exemplary heavy and light chain cross-sharing among affinity-matured antibodies in the ADT1-4(G04) lineage (0.4 nM human TRDV1 ELISA yields results ranked in a heat map). This "heat map" demonstrates the cross-sharing of CDR3 sequences among different affinity-matured antibodies in the ADT1-4 lineage and illustrates the affinity maturation process, which provides antibody sequences that do not necessarily need to be presented as specific heavy and light chain pairs. The results highlight that affinity-matured antibodies can cross-share light and heavy chains, and different LC / HC combinations yield equivalent or improved results in high-stringency antigen-binding studies. The ADT1-4(G04) parent clone is also included in the figure (bottom left). (B) Final selection of the ADT1-4 lineage: CDR3 usage and cross-sharing + cynomolgus antigen-binding "heat map" versus the starting parent ADT1-4 parent G04 mAb (bottom left). (C) ADT1-7 lineage final selection: CDR3 usage and cross-shared + human antigen binding "heatmap" versus the starting ADT1-7 parental E07 mAb (bottom left). [Figure 27B]CDR3 Usage and Cross-Sharing. (A) Exemplary heavy and light chain cross-sharing among affinity-matured antibodies in the ADT1-4(G04) lineage (0.4 nM human TRDV1 ELISA yields results ranked in a heat map). This "heat map" demonstrates the cross-sharing of CDR3 sequences among different affinity-matured antibodies in the ADT1-4 lineage and illustrates the affinity maturation process, which provides antibody sequences that do not necessarily need to be presented as specific heavy and light chain pairs. The results highlight that affinity-matured antibodies can cross-share light and heavy chains, and different LC / HC combinations yield equivalent or improved results in high-stringency antigen-binding studies. The ADT1-4(G04) parent clone is also included in the figure (bottom left). (B) Final selection of the ADT1-4 lineage: CDR3 usage and cross-sharing + cynomolgus antigen-binding "heat map" versus the starting parent ADT1-4 parent G04 mAb (bottom left). (C) ADT1-7 lineage final selection: CDR3 usage and cross-shared + human antigen binding "heatmap" versus the starting ADT1-7 parental E07 mAb (bottom left). [Figure 27C] CDR3 Usage and Cross-Sharing. (A) Exemplary heavy and light chain cross-sharing among affinity-matured antibodies in the ADT1-4(G04) lineage (0.4 nM human TRDV1 ELISA yields results ranked in a heat map). This "heat map" demonstrates the cross-sharing of CDR3 sequences among different affinity-matured antibodies in the ADT1-4 lineage and illustrates the affinity maturation process, which provides antibody sequences that do not necessarily need to be presented as specific heavy and light chain pairs. The results highlight that affinity-matured antibodies can cross-share light and heavy chains, and different LC / HC combinations yield equivalent or improved results in high-stringency antigen-binding studies. The ADT1-4(G04) parent clone is also included in the figure (bottom left). (B) Final selection of the ADT1-4 lineage: CDR3 usage and cross-sharing + cynomolgus antigen-binding "heat map" versus the starting parent ADT1-4 parent G04 mAb (bottom left). (C) ADT1-7 lineage final selection: CDR3 usage and cross-shared + human antigen binding "heatmap" versus the starting ADT1-7 parental E07 mAb (bottom left). [Figure 28]Fold enhancement of binding for ADT1-4 line compared to ADT1-4 parent G04. (A) Fold enhancement of recombinant human Vδ1 antigen binding. (B) Fold enhancement of recombinant cynomolgus monkey Vδ1 antigen binding. (C) Fold enhancement of primary Vδ1 MFI. (D) Fold enhancement of PEER Vδ1 cell line MFI. [Figure 29] Fold enhancement of binding to the ADT1-7 line compared to the ADT1-7 parent E07. (A). Fold enhancement of recombinant human Vδ1 antigen binding. (B). Fold enhancement of primary Vδ1 MFI. (C). Fold increase in PEER Vδ1 cell line MFI. [Figure 30A] Fold improvement in human (and cynomolgus) antigen binding versus parental clone. (A) Fold improvement in binding to human antigen. DELFIA ELISA signal of affinity matured clone versus parental ADT1-4 (G04), 0.4 nM recombinant human L1 antigen (containing human Vδ1 TCR antigen). (B) Fold improvement in binding to cynomolgus antigen (DV1 / GV77 containing cynomolgus SEQ ID NO: 308 (mature, minus leader)). DELFIA ELISA signal of affinity matured clone versus parental ADT1-4 (G04), 0.4 nM recombinant human L1 antigen. (C) Fold improvement in binding to human antigen. DELFIA ELISA signal of affinity matured clone versus parental ADT1-7 (E07), 0.4 nM recombinant human L1 antigen. [Figure 30B] Fold improvement in human (and cynomolgus) antigen binding versus parental clone. (A) Fold improvement in binding to human antigen. DELFIA ELISA signal of affinity matured clone versus parental ADT1-4 (G04), 0.4 nM recombinant human L1 antigen (containing human Vδ1 TCR antigen). (B) Fold improvement in binding to cynomolgus antigen (DV1 / GV77 containing cynomolgus SEQ ID NO: 308 (mature, minus leader)). DELFIA ELISA signal of affinity matured clone versus parental ADT1-4 (G04), 0.4 nM recombinant human L1 antigen. (C) Fold improvement in binding to human antigen. DELFIA ELISA signal of affinity matured clone versus parental ADT1-7 (E07), 0.4 nM recombinant human L1 antigen. [Figure 30C]Fold improvement in human (and cynomolgus) antigen binding versus parental clone. (A) Fold improvement in binding to human antigen. DELFIA ELISA signal of affinity matured clone versus parental ADT1-4 (G04), 0.4 nM recombinant human L1 antigen (containing human Vδ1 TCR antigen). (B) Fold improvement in binding to cynomolgus antigen (DV1 / GV77 containing cynomolgus SEQ ID NO: 308 (mature, minus leader)). DELFIA ELISA signal of affinity matured clone versus parental ADT1-4 (G04), 0.4 nM recombinant human L1 antigen. (C) Fold improvement in binding to human antigen. DELFIA ELISA signal of affinity matured clone versus parental ADT1-7 (E07), 0.4 nM recombinant human L1 antigen. [Figure 31A] Fold improvement in KD of human (and cynomolgus) antigens relative to the parental clone. (A) Fold improvement in human antigen KD of the ADT1-4(G04) lineage. (B) Fold improvement in cynomolgus antigen KD of the ADT1-4(G04) lineage. (C) Fold improvement in human antigen KD of the ADT1-7(E07) lineage. [Figure 31B] Fold improvement in KD of human (and cynomolgus) antigens relative to the parental clone. (A) Fold improvement in human antigen KD of the ADT1-4(G04) lineage. (B) Fold improvement in cynomolgus antigen KD of the ADT1-4(G04) lineage. (C) Fold improvement in human antigen KD of the ADT1-7(E07) lineage. [Figure 31C] Fold improvement in KD of human (and cynomolgus) antigens relative to the parental clone. (A) Fold improvement in human antigen KD of the ADT1-4(G04) lineage. (B) Fold improvement in cynomolgus antigen KD of the ADT1-4(G04) lineage. (C) Fold improvement in human antigen KD of the ADT1-7(E07) lineage. [Figure 32A] Binding affinity analysis (KD by SPR) for human Vδ1 antigen. (A) Surface plasmon resonance of the ADT1-4 line. (B) Surface plasmon resonance of the ADT1-7 line. (C) KD values ​​for the ADT1-4 line and fold change relative to the parental clone. (D) KD values ​​for the ADT1-7 line and fold change relative to the parental clone. (E) Fold change in KD relative to the parental clone for the ADT1-4 line. (F) Fold change in KD relative to the parental clone for the ADT1-7 line. [Figure 32B] Binding affinity analysis (KD by SPR) for human Vδ1 antigen. (A) Surface plasmon resonance of the ADT1-4 line. (B) Surface plasmon resonance of the ADT1-7 line. (C) KD values ​​for the ADT1-4 line and fold change relative to the parental clone. (D) KD values ​​for the ADT1-7 line and fold change relative to the parental clone. (E) Fold change in KD relative to the parental clone for the ADT1-4 line. (F) Fold change in KD relative to the parental clone for the ADT1-7 line. [Figure 32C] Binding affinity analysis (KD by SPR) for human Vδ1 antigen. (A) Surface plasmon resonance of the ADT1-4 line. (B) Surface plasmon resonance of the ADT1-7 line. (C) KD values ​​for the ADT1-4 line and fold change relative to the parental clone. (D) KD values ​​for the ADT1-7 line and fold change relative to the parental clone. (E) Fold change in KD relative to the parental clone for the ADT1-4 line. (F) Fold change in KD relative to the parental clone for the ADT1-7 line. [Figure 32D] Binding affinity analysis (KD by SPR) for human Vδ1 antigen. (A) Surface plasmon resonance of the ADT1-4 line. (B) Surface plasmon resonance of the ADT1-7 line. (C) KD values ​​for the ADT1-4 line and fold change relative to the parental clone. (D) KD values ​​for the ADT1-7 line and fold change relative to the parental clone. (E) Fold change in KD relative to the parental clone for the ADT1-4 line. (F) Fold change in KD relative to the parental clone for the ADT1-7 line. [Figure 32E] Binding affinity analysis (KD by SPR) for human Vδ1 antigen. (A) Surface plasmon resonance of the ADT1-4 line. (B) Surface plasmon resonance of the ADT1-7 line. (C) KD values ​​for the ADT1-4 line and fold change relative to the parental clone. (D) KD values ​​for the ADT1-7 line and fold change relative to the parental clone. (E) Fold change in KD relative to the parental clone for the ADT1-4 line. (F) Fold change in KD relative to the parental clone for the ADT1-7 line. [Figure 32F]Binding affinity analysis (KD by SPR) for human Vδ1 antigen. (A) Surface plasmon resonance of the ADT1-4 line. (B) Surface plasmon resonance of the ADT1-7 line. (C) KD values ​​for the ADT1-4 line and fold change relative to the parental clone. (D) KD values ​​for the ADT1-7 line and fold change relative to the parental clone. (E) Fold change in KD relative to the parental clone for the ADT1-4 line. (F) Fold change in KD relative to the parental clone for the ADT1-7 line. [Figure 33] Binding affinity analysis for cynomolgus monkey antigen (KD by SPR). (A) Surface plasmon resonance of ADT1-4 lineages against cynomolgus monkey antigen. (B) KD values ​​of ADT1-4 lineages against cynomolgus monkey antigen. [Figure 34A] Binding affinity to cell surface V51 TCR (EC50 for binding to cell surface V51). (A, B) Binding levels by V51 mAbs to two γδ T cell donors, ATS006 (A) and TS164 (B). (C) Bar graph showing the average 50% binding values ​​from ADT1-4 and ADT1-7 clones binding to V51-positive γδ T cells, expressed as the average of two donors; these values ​​are shown in the table along with the % improvement. (D) Table summarizing the IC50s plotted in (A) and (B), as well as V51-negative cell types, including various leukocyte subsets, including HEK293A, Raji cells, and primary blood mononuclear cells. For V51-positive γδ T cells, data are expressed as the average of two donors. [Figure 34B] Binding affinity to cell surface V51 TCR (EC50 for binding to cell surface V51). (A, B) Binding levels by V51 mAbs to two γδ T cell donors, ATS006 (A) and TS164 (B). (C) Bar graph showing the average 50% binding values ​​from ADT1-4 and ADT1-7 clones binding to V51-positive γδ T cells, expressed as the average of two donors; these values ​​are shown in the table along with the % improvement. (D) Table summarizing the IC50s plotted in (A) and (B), as well as V51-negative cell types, including various leukocyte subsets, including HEK293A, Raji cells, and primary blood mononuclear cells. For V51-positive γδ T cells, data are expressed as the average of two donors. [Figure 34C] Binding affinity to cell surface V51 TCR (EC50 for binding to cell surface V51). (A, B) Binding levels by V51 mAbs to two γδ T cell donors, ATS006 (A) and TS164 (B). (C) Bar graph showing the average 50% binding values ​​from ADT1-4 and ADT1-7 clones binding to V51-positive γδ T cells, expressed as the average of two donors; these values ​​are shown in the table along with the % improvement. (D) Table summarizing the IC50s plotted in (A) and (B), as well as V51-negative cell types, including various leukocyte subsets, including HEK293A, Raji cells, and primary blood mononuclear cells. For V51-positive γδ T cells, data are expressed as the average of two donors. [Figure 34D] Binding affinity to cell surface V51 TCR (EC50 for binding to cell surface V51). (A, B) Binding levels by V51 mAbs to two γδ T cell donors, ATS006 (A) and TS164 (B). (C) Bar graph showing the average 50% binding values ​​from ADT1-4 and ADT1-7 clones binding to V51-positive γδ T cells, expressed as the average of two donors; these values ​​are shown in the table along with the % improvement. (D) Table summarizing the IC50s plotted in (A) and (B), as well as V51-negative cell types, including various leukocyte subsets, including HEK293A, Raji cells, and primary blood mononuclear cells. For V51-positive γδ T cells, data are expressed as the average of two donors. [Figure 35A] TCR downregulation (by soluble antibodies). (A, B) ADT1-4 lineage (A) and ADT1-7 lineage (B). (C) Mean TCR downregulation-IC50 obtained from two GD cell donors. (D, E) Improved fold TCR downregulation from the parental ADT1-4 clone (D) and ADT1-7 clone (E). (F) Median efficacy values ​​from (C) calculated for the percentage improvement from each parent of ADT1-4 (top) and ADT1-7 (bottom). (G) Median efficacy values ​​from (C) calculated for the fold improvement from each parent of ADT1-4 (top) and ADT1-7 (bottom). [Figure 35B]TCR downregulation (by soluble antibodies). (A, B) ADT1-4 lineage (A) and ADT1-7 lineage (B). (C) Mean TCR downregulation-IC50 obtained from two GD cell donors. (D, E) Improved fold TCR downregulation from the parental ADT1-4 clone (D) and ADT1-7 clone (E). (F) Median efficacy values ​​from (C) calculated for the percentage improvement from each parent of ADT1-4 (top) and ADT1-7 (bottom). (G) Median efficacy values ​​from (C) calculated for the fold improvement from each parent of ADT1-4 (top) and ADT1-7 (bottom). [Figure 35C] TCR downregulation (by soluble antibodies). (A, B) ADT1-4 lineage (A) and ADT1-7 lineage (B). (C) Mean TCR downregulation-IC50 obtained from two GD cell donors. (D, E) Improved fold TCR downregulation from the parental ADT1-4 clone (D) and ADT1-7 clone (E). (F) Median efficacy values ​​from (C) calculated for the percentage improvement from each parent of ADT1-4 (top) and ADT1-7 (bottom). (G) Median efficacy values ​​from (C) calculated for the fold improvement from each parent of ADT1-4 (top) and ADT1-7 (bottom). [Figure 35D] TCR downregulation (by soluble antibodies). (A, B) ADT1-4 lineage (A) and ADT1-7 lineage (B). (C) Mean TCR downregulation-IC50 obtained from two GD cell donors. (D, E) Improved fold TCR downregulation from the parental ADT1-4 clone (D) and ADT1-7 clone (E). (F) Median efficacy values ​​from (C) calculated for the percentage improvement from each parent of ADT1-4 (top) and ADT1-7 (bottom). (G) Median efficacy values ​​from (C) calculated for the fold improvement from each parent of ADT1-4 (top) and ADT1-7 (bottom). [Figure 35E]TCR downregulation (by soluble antibodies). (A, B) ADT1-4 lineage (A) and ADT1-7 lineage (B). (C) Mean TCR downregulation-IC50 obtained from two GD cell donors. (D, E) Improved fold TCR downregulation from the parental ADT1-4 clone (D) and ADT1-7 clone (E). (F) Median efficacy values ​​from (C) calculated for the percentage improvement from each parent of ADT1-4 (top) and ADT1-7 (bottom). (G) Median efficacy values ​​from (C) calculated for the fold improvement from each parent of ADT1-4 (top) and ADT1-7 (bottom). [Figure 35F] TCR downregulation (by soluble antibodies). (A, B) ADT1-4 lineage (A) and ADT1-7 lineage (B). (C) Mean TCR downregulation-IC50 obtained from two GD cell donors. (D, E) Improved fold TCR downregulation from the parental ADT1-4 clone (D) and ADT1-7 clone (E). (F) Median efficacy values ​​from (C) calculated for the percentage improvement from each parent of ADT1-4 (top) and ADT1-7 (bottom). (G) Median efficacy values ​​from (C) calculated for the fold improvement from each parent of ADT1-4 (top) and ADT1-7 (bottom). [Figure 35G] TCR downregulation (by soluble antibodies). (A, B) ADT1-4 lineage (A) and ADT1-7 lineage (B). (C) Mean TCR downregulation-IC50 obtained from two GD cell donors. (D, E) Improved fold TCR downregulation from the parental ADT1-4 clone (D) and ADT1-7 clone (E). (F) Median efficacy values ​​from (C) calculated for the percentage improvement from each parent of ADT1-4 (top) and ADT1-7 (bottom). (G) Median efficacy values ​​from (C) calculated for the fold improvement from each parent of ADT1-4 (top) and ADT1-7 (bottom). [Figure 36A]Vδ1 monoclonal antibody on γδ activation as measured by CD107a expression. (A, B) ADT1-4-2 clone in GD cells alone (A) or with THP-1 cells (B). (C, D) ADT1-7-3 clone in GD cells alone (C) or with THP-1 cells (D). (E) Table showing the percent increase in γδ CD107a expression from co-cultured cells treated with the highest concentration of Vδ1 mAb compared to untreated, non-co-cultured γδ cells. (F) Table showing the percent increase in γδ CD107a expression from co-cultured cells treated with the highest concentration of Vδ1 mAb compared to untreated, co-cultured, and non-co-cultured γδ cells. [Figure 36B] Vδ1 monoclonal antibody on γδ activation as measured by CD107a expression. (A, B) ADT1-4-2 clone in GD cells alone (A) or with THP-1 cells (B). (C, D) ADT1-7-3 clone in GD cells alone (C) or with THP-1 cells (D). (E) Table showing the percent increase in γδ CD107a expression from co-cultured cells treated with the highest concentration of Vδ1 mAb compared to untreated, non-co-cultured γδ cells. (F) Table showing the percent increase in γδ CD107a expression from co-cultured cells treated with the highest concentration of Vδ1 mAb compared to untreated, co-cultured, and non-co-cultured γδ cells. [Figure 36C] Vδ1 monoclonal antibody on γδ activation as measured by CD107a expression. (A, B) ADT1-4-2 clone in GD cells alone (A) or with THP-1 cells (B). (C, D) ADT1-7-3 clone in GD cells alone (C) or with THP-1 cells (D). (E) Table showing the percent increase in γδ CD107a expression from co-cultured cells treated with the highest concentration of Vδ1 mAb compared to untreated, non-co-cultured γδ cells. (F) Table showing the percent increase in γδ CD107a expression from co-cultured cells treated with the highest concentration of Vδ1 mAb compared to untreated, co-cultured, and non-co-cultured γδ cells. [Figure 36D]Vδ1 monoclonal antibody on γδ activation as measured by CD107a expression. (A, B) ADT1-4-2 clone in GD cells alone (A) or with THP-1 cells (B). (C, D) ADT1-7-3 clone in GD cells alone (C) or with THP-1 cells (D). (E) Table showing the percent increase in γδ CD107a expression from co-cultured cells treated with the highest concentration of Vδ1 mAb compared to untreated, non-co-cultured γδ cells. (F) Table showing the percent increase in γδ CD107a expression from co-cultured cells treated with the highest concentration of Vδ1 mAb compared to untreated, co-cultured, and non-co-cultured γδ cells. [Figure 36E] Vδ1 monoclonal antibody on γδ activation as measured by CD107a expression. (A, B) ADT1-4-2 clone in GD cells alone (A) or with THP-1 cells (B). (C, D) ADT1-7-3 clone in GD cells alone (C) or with THP-1 cells (D). (E) Table showing the percent increase in γδ CD107a expression from co-cultured cells treated with the highest concentration of Vδ1 mAb compared to untreated, non-co-cultured γδ cells. (F) Table showing the percent increase in γδ CD107a expression from co-cultured cells treated with the highest concentration of Vδ1 mAb compared to untreated, co-cultured, and non-co-cultured γδ cells. [Figure 36F] Vδ1 monoclonal antibody on γδ activation as measured by CD107a expression. (A, B) ADT1-4-2 clone in GD cells alone (A) or with THP-1 cells (B). (C, D) ADT1-7-3 clone in GD cells alone (C) or with THP-1 cells (D). (E) Table showing the percent increase in γδ CD107a expression from co-cultured cells treated with the highest concentration of Vδ1 mAb compared to untreated, non-co-cultured γδ cells. (F) Table showing the percent increase in γδ CD107a expression from co-cultured cells treated with the highest concentration of Vδ1 mAb compared to untreated, co-cultured, and non-co-cultured γδ cells. [Figure 37A]Vδ1 monoclonal antibody on γδ activation as measured by CD25 expression. (A, B) ADT1-4-2 clone in GD cells alone (A) or with THP-1 cells (B). (C, D) ADT1-7-3 clone in GD cells alone (C) or with THP-1 cells (D). (E) Table showing the percent increase in γδ CD25 expression from co-cultured cells treated with the highest concentration of Vδ1 mAb compared to untreated, non-co-cultured γδ cells. (F) Table showing the percent increase in γδ CD25 expression from co-cultured cells treated with the highest concentration of Vδ1 mAb compared to untreated, co-cultured, and non-co-cultured γδ cells. [Figure 37B] Vδ1 monoclonal antibody on γδ activation as measured by CD25 expression. (A, B) ADT1-4-2 clone in GD cells alone (A) or with THP-1 cells (B). (C, D) ADT1-7-3 clone in GD cells alone (C) or with THP-1 cells (D). (E) Table showing the percent increase in γδ CD25 expression from co-cultured cells treated with the highest concentration of Vδ1 mAb compared to untreated, non-co-cultured γδ cells. (F) Table showing the percent increase in γδ CD25 expression from co-cultured cells treated with the highest concentration of Vδ1 mAb compared to untreated, co-cultured, and non-co-cultured γδ cells. [Figure 37C] Vδ1 monoclonal antibody on γδ activation as measured by CD25 expression. (A, B) ADT1-4-2 clone in GD cells alone (A) or with THP-1 cells (B). (C, D) ADT1-7-3 clone in GD cells alone (C) or with THP-1 cells (D). (E) Table showing the percent increase in γδ CD25 expression from co-cultured cells treated with the highest concentration of Vδ1 mAb compared to untreated, non-co-cultured γδ cells. (F) Table showing the percent increase in γδ CD25 expression from co-cultured cells treated with the highest concentration of Vδ1 mAb compared to untreated, co-cultured, and non-co-cultured γδ cells. [Figure 37D]Vδ1 monoclonal antibody on γδ activation as measured by CD25 expression. (A, B) ADT1-4-2 clone in GD cells alone (A) or with THP-1 cells (B). (C, D) ADT1-7-3 clone in GD cells alone (C) or with THP-1 cells (D). (E) Table showing the percent increase in γδ CD25 expression from co-cultured cells treated with the highest concentration of Vδ1 mAb compared to untreated, non-co-cultured γδ cells. (F) Table showing the percent increase in γδ CD25 expression from co-cultured cells treated with the highest concentration of Vδ1 mAb compared to untreated, co-cultured, and non-co-cultured γδ cells. [Figure 37E] Vδ1 monoclonal antibody on γδ activation as measured by CD25 expression. (A, B) ADT1-4-2 clone in GD cells alone (A) or with THP-1 cells (B). (C, D) ADT1-7-3 clone in GD cells alone (C) or with THP-1 cells (D). (E) Table showing the percent increase in γδ CD25 expression from co-cultured cells treated with the highest concentration of Vδ1 mAb compared to untreated, non-co-cultured γδ cells. (F) Table showing the percent increase in γδ CD25 expression from co-cultured cells treated with the highest concentration of Vδ1 mAb compared to untreated, co-cultured, and non-co-cultured γδ cells. [Figure 37F] Vδ1 monoclonal antibody on γδ activation as measured by CD25 expression. (A, B) ADT1-4-2 clone in GD cells alone (A) or with THP-1 cells (B). (C, D) ADT1-7-3 clone in GD cells alone (C) or with THP-1 cells (D). (E) Table showing the percent increase in γδ CD25 expression from co-cultured cells treated with the highest concentration of Vδ1 mAb compared to untreated, non-co-cultured γδ cells. (F) Table showing the percent increase in γδ CD25 expression from co-cultured cells treated with the highest concentration of Vδ1 mAb compared to untreated, co-cultured, and non-co-cultured γδ cells. [Figure 38A]Cynomolgus TCR downregulation (by soluble antibodies). (A) Comparison of the ability of ADT1-4-2 and ADT1-4 to engage and reduce expression of VD1 on cynomolgus γδ-T cells. (B) Percent cell surface expression of VD1 upon treatment with ADT1-4-2. (C) Individual EC50 values ​​of different donors combined with mean and standard deviation. (D-G) Additional studies performed with whole blood samples from cynomolgus monkeys (n=5). [Figure 38B] Cynomolgus TCR downregulation (by soluble antibodies). (A) Comparison of the ability of ADT1-4-2 and ADT1-4 to engage and reduce expression of VD1 on cynomolgus γδ-T cells. (B) Percent cell surface expression of VD1 upon treatment with ADT1-4-2. (C) Individual EC50 values ​​of different donors combined with mean and standard deviation. (D-G) Additional studies performed with whole blood samples from cynomolgus monkeys (n=5). [Figure 38C] Cynomolgus TCR downregulation (by soluble antibodies). (A) Comparison of the ability of ADT1-4-2 and ADT1-4 to engage and reduce expression of VD1 on cynomolgus γδ-T cells. (B) Percent cell surface expression of VD1 upon treatment with ADT1-4-2. (C) Individual EC50 values ​​of different donors combined with mean and standard deviation. (D-G) Additional studies performed with whole blood samples from cynomolgus monkeys (n=5). [Figure 38D] Cynomolgus TCR downregulation (by soluble antibodies). (A) Comparison of the ability of ADT1-4-2 and ADT1-4 to engage and reduce expression of VD1 on cynomolgus γδ-T cells. (B) Percent cell surface expression of VD1 upon treatment with ADT1-4-2. (C) Individual EC50 values ​​of different donors combined with mean and standard deviation. (D-G) Additional studies performed with whole blood samples from cynomolgus monkeys (n=5). [Figure 38E]Cynomolgus TCR downregulation (by soluble antibodies). (A) Comparison of the ability of ADT1-4-2 and ADT1-4 to engage and reduce expression of VD1 on cynomolgus γδ-T cells. (B) Percent cell surface expression of VD1 upon treatment with ADT1-4-2. (C) Individual EC50 values ​​of different donors combined with mean and standard deviation. (D-G) Additional studies performed with whole blood samples from cynomolgus monkeys (n=5). [Figure 38F] Cynomolgus TCR downregulation (by soluble antibodies). (A) Comparison of the ability of ADT1-4-2 and ADT1-4 to engage and reduce expression of VD1 on cynomolgus γδ-T cells. (B) Percent cell surface expression of VD1 upon treatment with ADT1-4-2. (C) Individual EC50 values ​​of different donors combined with mean and standard deviation. (D-G) Additional studies performed with whole blood samples from cynomolgus monkeys (n=5). [Figure 38G] Cynomolgus TCR downregulation (by soluble antibodies). (A) Comparison of the ability of ADT1-4-2 and ADT1-4 to engage and reduce expression of VD1 on cynomolgus γδ-T cells. (B) Percent cell surface expression of VD1 upon treatment with ADT1-4-2. (C) Individual EC50 values ​​of different donors combined with mean and standard deviation. (D-G) Additional studies performed with whole blood samples from cynomolgus monkeys (n=5). [Figure 39A] Quantification of viable THP-1 cell numbers after 24 h of co-culture with γδT cells in the presence of Vδ1 mAb or control. (A) THP-1 cytotoxicity assay for the ADT1-4 clone. (B) THP-1 cytotoxicity assay for the ADT1-7 clone. (C) Mean EC50 in the THP-1 cytotoxicity assay for the ADT1-4 and ADT1-7 clones. (D) Table summarizing the EC50s plotted in (C). [Figure 39B]Quantification of viable THP-1 cell numbers after 24 h of co-culture with γδT cells in the presence of Vδ1 mAb or control. (A) THP-1 cytotoxicity assay for the ADT1-4 clone. (B) THP-1 cytotoxicity assay for the ADT1-7 clone. (C) Mean EC50 in the THP-1 cytotoxicity assay for the ADT1-4 and ADT1-7 clones. (D) Table summarizing the EC50s plotted in (C). [Figure 39C] Quantification of viable THP-1 cell numbers after 24 h of co-culture with γδT cells in the presence of Vδ1 mAb or control. (A) THP-1 cytotoxicity assay for the ADT1-4 clone. (B) THP-1 cytotoxicity assay for the ADT1-7 clone. (C) Mean EC50 in the THP-1 cytotoxicity assay for the ADT1-4 and ADT1-7 clones. (D) Table summarizing the EC50s plotted in (C). [Figure 39D] Quantification of viable THP-1 cell numbers after 24 h of co-culture with γδT cells in the presence of Vδ1 mAb or control. (A) THP-1 cytotoxicity assay for the ADT1-4 clone. (B) THP-1 cytotoxicity assay for the ADT1-7 clone. (C) Mean EC50 in the THP-1 cytotoxicity assay for the ADT1-4 and ADT1-7 clones. (D) Table summarizing the EC50s plotted in (C). [Figure 40] Vδ1 monoclonal antibody for antibody-dependent cellular cytotoxicity (ADCC). [Figure 41] Vδ1 monoclonal antibody against complement-dependent cytotoxicity (CDC). [Figure 42] Healthy cell preservation of clone ADT1-4-2. [Figure 43A]Effect of anti-Vδ1 antibodies on TIL populations derived from primary tumor biopsies. (A, B) Percent reduction in Vδ1 TCR expression on total tumor-infiltrating γδ T cells after 48 (A) or 72 (B) hours of mAb stimulation in two separate donors, confirming target engagement in each case. (C) Enhanced expression of both CD25 and Ki67 on Vδ1+ T cells after 48 hours of stimulation with ADT1-4-2 compared with stimulation with IgG1 isotype control or ADT1-4. (D) Substantial fold increase in IFN-γ production by TILs stimulated with ADT1-4-2 or ADT1-7-3 for 72 hours in the presence of 50 ng / ml IL-15. (E) Stimulation of TILs with ADT1-4-2 or ADT1-7-3 did not enhance secretion of the type 17-associated cytokines IL-6 or IL-17 at this time point. (F, G) Percent reduction in Vδ1 TCR expression on total tumor-infiltrating γδ T cells after 24 (F) or 72 (G) hours of mAb stimulation in two individual donors, confirming target engagement in TILs isolated by enzymatic digestion. (H) Dose-dependent enhancement of Ki67 expression on γδ T cells after 72 hours of stimulation with ADT1-4-2. (I, J) Fold increase in IFN-γ produced by TILs isolated from two individual donors by enzymatic digestion and stimulated with ADT1-4-2 at a concentration of 6.66 nM in the presence of 2 ng / ml IL-15 for 24 (I) or 72 (J) hours. In all cases, the concentrations of control anti-RSV and parental ADT1-4 match the highest concentrations used in the study (i.e., 6.66 nM for A, C, F, G, H, I, J, and 66.6 nM for B and E). [Figure 43B]Effect of anti-Vδ1 antibodies on TIL populations derived from primary tumor biopsies. (A, B) Percent reduction in Vδ1 TCR expression on total tumor-infiltrating γδ T cells after 48 (A) or 72 (B) hours of mAb stimulation in two separate donors, confirming target engagement in each case. (C) Enhanced expression of both CD25 and Ki67 on Vδ1+ T cells after 48 hours of stimulation with ADT1-4-2 compared with stimulation with IgG1 isotype control or ADT1-4. (D) Substantial fold increase in IFN-γ production by TILs stimulated with ADT1-4-2 or ADT1-7-3 for 72 hours in the presence of 50 ng / ml IL-15. (E) Stimulation of TILs with ADT1-4-2 or ADT1-7-3 did not enhance secretion of the type 17-associated cytokines IL-6 or IL-17 at this time point. (F, G) Percent reduction in Vδ1 TCR expression on total tumor-infiltrating γδ T cells after 24 (F) or 72 (G) hours of mAb stimulation in two individual donors, confirming target engagement in TILs isolated by enzymatic digestion. (H) Dose-dependent enhancement of Ki67 expression on γδ T cells after 72 hours of stimulation with ADT1-4-2. (I, J) Fold increase in IFN-γ produced by TILs isolated from two individual donors by enzymatic digestion and stimulated with ADT1-4-2 at a concentration of 6.66 nM in the presence of 2 ng / ml IL-15 for 24 (I) or 72 (J) hours. In all cases, the concentrations of control anti-RSV and parental ADT1-4 match the highest concentrations used in the study (i.e., 6.66 nM for A, C, F, G, H, I, J, and 66.6 nM for B and E). [Figure 43C]Effect of anti-Vδ1 antibodies on TIL populations derived from primary tumor biopsies. (A, B) Percent reduction in Vδ1 TCR expression on total tumor-infiltrating γδ T cells after 48 (A) or 72 (B) hours of mAb stimulation in two separate donors, confirming target engagement in each case. (C) Enhanced expression of both CD25 and Ki67 on Vδ1+ T cells after 48 hours of stimulation with ADT1-4-2 compared with stimulation with IgG1 isotype control or ADT1-4. (D) Substantial fold increase in IFN-γ production by TILs stimulated with ADT1-4-2 or ADT1-7-3 for 72 hours in the presence of 50 ng / ml IL-15. (E) Stimulation of TILs with ADT1-4-2 or ADT1-7-3 did not enhance secretion of the type 17-associated cytokines IL-6 or IL-17 at this time point. (F, G) Percent reduction in Vδ1 TCR expression on total tumor-infiltrating γδ T cells after 24 (F) or 72 (G) hours of mAb stimulation in two individual donors, confirming target engagement in TILs isolated by enzymatic digestion. (H) Dose-dependent enhancement of Ki67 expression on γδ T cells after 72 hours of stimulation with ADT1-4-2. (I, J) Fold increase in IFN-γ produced by TILs isolated from two individual donors by enzymatic digestion and stimulated with ADT1-4-2 at a concentration of 6.66 nM in the presence of 2 ng / ml IL-15 for 24 (I) or 72 (J) hours. In all cases, the concentrations of control anti-RSV and parental ADT1-4 match the highest concentrations used in the study (i.e., 6.66 nM for A, C, F, G, H, I, J, and 66.6 nM for B and E). [Figure 43D]Effect of anti-Vδ1 antibodies on TIL populations derived from primary tumor biopsies. (A, B) Percent reduction in Vδ1 TCR expression on total tumor-infiltrating γδ T cells after 48 (A) or 72 (B) hours of mAb stimulation in two separate donors, confirming target engagement in each case. (C) Enhanced expression of both CD25 and Ki67 on Vδ1+ T cells after 48 hours of stimulation with ADT1-4-2 compared with stimulation with IgG1 isotype control or ADT1-4. (D) Substantial fold increase in IFN-γ production by TILs stimulated with ADT1-4-2 or ADT1-7-3 for 72 hours in the presence of 50 ng / ml IL-15. (E) Stimulation of TILs with ADT1-4-2 or ADT1-7-3 did not enhance secretion of the type 17-associated cytokines IL-6 or IL-17 at this time point. (F, G) Percent reduction in Vδ1 TCR expression on total tumor-infiltrating γδ T cells after 24 (F) or 72 (G) hours of mAb stimulation in two individual donors, confirming target engagement in TILs isolated by enzymatic digestion. (H) Dose-dependent enhancement of Ki67 expression on γδ T cells after 72 hours of stimulation with ADT1-4-2. (I, J) Fold increase in IFN-γ produced by TILs isolated from two individual donors by enzymatic digestion and stimulated with ADT1-4-2 at a concentration of 6.66 nM in the presence of 2 ng / ml IL-15 for 24 (I) or 72 (J) hours. In all cases, the concentrations of control anti-RSV and parental ADT1-4 match the highest concentrations used in the study (i.e., 6.66 nM for A, C, F, G, H, I, J, and 66.6 nM for B and E). [Figure 43E]Effect of anti-Vδ1 antibodies on TIL populations derived from primary tumor biopsies. (A, B) Percent reduction in Vδ1 TCR expression on total tumor-infiltrating γδ T cells after 48 (A) or 72 (B) hours of mAb stimulation in two separate donors, confirming target engagement in each case. (C) Enhanced expression of both CD25 and Ki67 on Vδ1+ T cells after 48 hours of stimulation with ADT1-4-2 compared with stimulation with IgG1 isotype control or ADT1-4. (D) Substantial fold increase in IFN-γ production by TILs stimulated with ADT1-4-2 or ADT1-7-3 for 72 hours in the presence of 50 ng / ml IL-15. (E) Stimulation of TILs with ADT1-4-2 or ADT1-7-3 did not enhance secretion of the type 17-associated cytokines IL-6 or IL-17 at this time point. (F, G) Percent reduction in Vδ1 TCR expression on total tumor-infiltrating γδ T cells after 24 (F) or 72 (G) hours of mAb stimulation in two individual donors, confirming target engagement in TILs isolated by enzymatic digestion. (H) Dose-dependent enhancement of Ki67 expression on γδ T cells after 72 hours of stimulation with ADT1-4-2. (I, J) Fold increase in IFN-γ produced by TILs isolated from two individual donors by enzymatic digestion and stimulated with ADT1-4-2 at a concentration of 6.66 nM in the presence of 2 ng / ml IL-15 for 24 (I) or 72 (J) hours. In all cases, the concentrations of control anti-RSV and parental ADT1-4 match the highest concentrations used in the study (i.e., 6.66 nM for A, C, F, G, H, I, J, and 66.6 nM for B and E). [Figure 43F]Effect of anti-Vδ1 antibodies on TIL populations derived from primary tumor biopsies. (A, B) Percent reduction in Vδ1 TCR expression on total tumor-infiltrating γδ T cells after 48 (A) or 72 (B) hours of mAb stimulation in two separate donors, confirming target engagement in each case. (C) Enhanced expression of both CD25 and Ki67 on Vδ1+ T cells after 48 hours of stimulation with ADT1-4-2 compared with stimulation with IgG1 isotype control or ADT1-4. (D) Substantial fold increase in IFN-γ production by TILs stimulated with ADT1-4-2 or ADT1-7-3 for 72 hours in the presence of 50 ng / ml IL-15. (E) Stimulation of TILs with ADT1-4-2 or ADT1-7-3 did not enhance secretion of the type 17-associated cytokines IL-6 or IL-17 at this time point. (F, G) Percent reduction in Vδ1 TCR expression on total tumor-infiltrating γδ T cells after 24 (F) or 72 (G) hours of mAb stimulation in two individual donors, confirming target engagement in TILs isolated by enzymatic digestion. (H) Dose-dependent enhancement of Ki67 expression on γδ T cells after 72 hours of stimulation with ADT1-4-2. (I, J) Fold increase in IFN-γ produced by TILs isolated from two individual donors by enzymatic digestion and stimulated with ADT1-4-2 at a concentration of 6.66 nM in the presence of 2 ng / ml IL-15 for 24 (I) or 72 (J) hours. In all cases, the concentrations of control anti-RSV and parental ADT1-4 match the highest concentrations used in the study (i.e., 6.66 nM for A, C, F, G, H, I, J, and 66.6 nM for B and E). [Figure 43G]Effect of anti-Vδ1 antibodies on TIL populations derived from primary tumor biopsies. (A, B) Percent reduction in Vδ1 TCR expression on total tumor-infiltrating γδ T cells after 48 (A) or 72 (B) hours of mAb stimulation in two separate donors, confirming target engagement in each case. (C) Enhanced expression of both CD25 and Ki67 on Vδ1+ T cells after 48 hours of stimulation with ADT1-4-2 compared with stimulation with IgG1 isotype control or ADT1-4. (D) Substantial fold increase in IFN-γ production by TILs stimulated with ADT1-4-2 or ADT1-7-3 for 72 hours in the presence of 50 ng / ml IL-15. (E) Stimulation of TILs with ADT1-4-2 or ADT1-7-3 did not enhance secretion of the type 17-associated cytokines IL-6 or IL-17 at this time point. (F, G) Percent reduction in Vδ1 TCR expression on total tumor-infiltrating γδ T cells after 24 (F) or 72 (G) hours of mAb stimulation in two individual donors, confirming target engagement in TILs isolated by enzymatic digestion. (H) Dose-dependent enhancement of Ki67 expression on γδ T cells after 72 hours of stimulation with ADT1-4-2. (I, J) Fold increase in IFN-γ produced by TILs isolated from two individual donors by enzymatic digestion and stimulated with ADT1-4-2 at a concentration of 6.66 nM in the presence of 2 ng / ml IL-15 for 24 (I) or 72 (J) hours. In all cases, the concentrations of control anti-RSV and parental ADT1-4 match the highest concentrations used in the study (i.e., 6.66 nM for A, C, F, G, H, I, J, and 66.6 nM for B and E). [Figure 43H]Effect of anti-Vδ1 antibodies on TIL populations derived from primary tumor biopsies. (A, B) Percent reduction in Vδ1 TCR expression on total tumor-infiltrating γδ T cells after 48 (A) or 72 (B) hours of mAb stimulation in two separate donors, confirming target engagement in each case. (C) Enhanced expression of both CD25 and Ki67 on Vδ1+ T cells after 48 hours of stimulation with ADT1-4-2 compared with stimulation with IgG1 isotype control or ADT1-4. (D) Substantial fold increase in IFN-γ production by TILs stimulated with ADT1-4-2 or ADT1-7-3 for 72 hours in the presence of 50 ng / ml IL-15. (E) Stimulation of TILs with ADT1-4-2 or ADT1-7-3 did not enhance secretion of the type 17-associated cytokines IL-6 or IL-17 at this time point. (F, G) Percent reduction in Vδ1 TCR expression on total tumor-infiltrating γδ T cells after 24 (F) or 72 (G) hours of mAb stimulation in two individual donors, confirming target engagement in TILs isolated by enzymatic digestion. (H) Dose-dependent enhancement of Ki67 expression on γδ T cells after 72 hours of stimulation with ADT1-4-2. (I, J) Fold increase in IFN-γ produced by TILs isolated from two individual donors by enzymatic digestion and stimulated with ADT1-4-2 at a concentration of 6.66 nM in the presence of 2 ng / ml IL-15 for 24 (I) or 72 (J) hours. In all cases, the concentrations of control anti-RSV and parental ADT1-4 match the highest concentrations used in the study (i.e., 6.66 nM for A, C, F, G, H, I, J, and 66.6 nM for B and E). [Figure 43I]Effect of anti-Vδ1 antibodies on TIL populations derived from primary tumor biopsies. (A, B) Percent reduction in Vδ1 TCR expression on total tumor-infiltrating γδ T cells after 48 (A) or 72 (B) hours of mAb stimulation in two separate donors, confirming target engagement in each case. (C) Enhanced expression of both CD25 and Ki67 on Vδ1+ T cells after 48 hours of stimulation with ADT1-4-2 compared with stimulation with IgG1 isotype control or ADT1-4. (D) Substantial fold increase in IFN-γ production by TILs stimulated with ADT1-4-2 or ADT1-7-3 for 72 hours in the presence of 50 ng / ml IL-15. (E) Stimulation of TILs with ADT1-4-2 or ADT1-7-3 did not enhance secretion of the type 17-associated cytokines IL-6 or IL-17 at this time point. (F, G) Percent reduction in Vδ1 TCR expression on total tumor-infiltrating γδ T cells after 24 (F) or 72 (G) hours of mAb stimulation in two individual donors, confirming target engagement in TILs isolated by enzymatic digestion. (H) Dose-dependent enhancement of Ki67 expression on γδ T cells after 72 hours of stimulation with ADT1-4-2. (I, J) Fold increase in IFN-γ produced by TILs isolated from two individual donors by enzymatic digestion and stimulated with ADT1-4-2 at a concentration of 6.66 nM in the presence of 2 ng / ml IL-15 for 24 (I) or 72 (J) hours. In all cases, the concentrations of control anti-RSV and parental ADT1-4 match the highest concentrations used in the study (i.e., 6.66 nM for A, C, F, G, H, I, J, and 66.6 nM for B and E). [Figure 43J]Effect of anti-Vδ1 antibodies on TIL populations derived from primary tumor biopsies. (A, B) Percent reduction in Vδ1 TCR expression on total tumor-infiltrating γδ T cells after 48 (A) or 72 (B) hours of mAb stimulation in two separate donors, confirming target engagement in each case. (C) Enhanced expression of both CD25 and Ki67 on Vδ1+ T cells after 48 hours of stimulation with ADT1-4-2 compared with stimulation with IgG1 isotype control or ADT1-4. (D) Substantial fold increase in IFN-γ production by TILs stimulated with ADT1-4-2 or ADT1-7-3 for 72 hours in the presence of 50 ng / ml IL-15. (E) Stimulation of TILs with ADT1-4-2 or ADT1-7-3 did not enhance secretion of the type 17-associated cytokines IL-6 or IL-17 at this time point. (F, G) Percent reduction in Vδ1 TCR expression on total tumor-infiltrating γδ T cells after 24 (F) or 72 (G) hours of mAb stimulation in two individual donors, confirming target engagement in TILs isolated by enzymatic digestion. (H) Dose-dependent enhancement of Ki67 expression on γδ T cells after 72 hours of stimulation with ADT1-4-2. (I, J) Fold increase in IFN-γ produced by TILs isolated from two individual donors by enzymatic digestion and stimulated with ADT1-4-2 at a concentration of 6.66 nM in the presence of 2 ng / ml IL-15 for 24 (I) or 72 (J) hours. In all cases, the concentrations of control anti-RSV and parental ADT1-4 match the highest concentrations used in the study (i.e., 6.66 nM for A, C, F, G, H, I, J, and 66.6 nM for B and E). [Figure 44]The effect of anti-Vδ1 antibodies on TIL populations from primary tumor biopsies. (A) Enhanced expression of CD25 and Ki67 in γδ T cells stimulated with ADT1-4-2 for 10 days is shown. (B) Substantial increase in perforin+ granzyme B+ γδ T cells after 10 days of stimulation with ADT1-4-2 is shown. (C) Significant enhancement of granzyme B and perforin expression by both CD8+ and CD8- αβ T cells after 10 days of stimulation of tumor-infiltrating Vδ1+ T cells with ADT1-4-2 is shown. (D) Significant increase in IFN-γ production by lung tumor-derived TILs after stimulation with ADT1-4-2, and moderate increase in IL-17 and IL-6 production is shown. I demonstrates enhanced production of the chemokines CCL2, CCL4, and CXCL10 by TILs after 10 days of stimulation with ADT1-4-2. In all cases, the control anti-RSV and parental ADT1-4 were matched to the same concentrations as the affinity matured ADT1-4-2. [Figure 45] ADT1-4 lineage clone (light chain) sequence [Figure 46] Sequence of ADT1-4 lineage clone (heavy chain). [Figure 47] Sequence of ADT1-7 lineage clone (light chain). [Figure 48] Sequence of the ADT1-7 lineage clone (heavy chain). [Figure 49] The anti-V51 / CD19 bispecific antibody exhibits high-affinity binding to human V51 and cynomolgus V51, comparable to the parent monoclonal V51 mAb. Surface plasmon resonance (SPR) analysis was performed with the ADT1-4-2 / CD19 bispecific agent to assess binding to human V51 and CD19 antigens. The bispecific antibody binds to both human and cynomolgus V51 with only a slight reduction in affinity for both antigens. [Figure 50A]Vδ1-CD19 bispecific T cell engagers enhance CD19+ target cytotoxicity and γδ T cell activation while sparing healthy CD19+ B cells. (A) CD19 expression on cancerous NALM-6 and Raji cells, as well as primary B cells and Vδ1 γδ T cells, as determined by flow cytometry. (B-D) Effect of parental (ADT1-4) and affinity-matured (ADT1-4-2) Vδ1-CD19 bispecifics on NALM-6 cells (B), Raji cells (C), and B cell cytotoxicity (D). Antibodies were titrated over 12 h in the presence of Vδ1 γδ T cells at a 1:1 E:T ratio. The percentage of viable cells was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of Vδ1 γδ T cells. (E) Bar graph representing the percentage of viable cells after 12 h of co-culture of Vδ1 γδ T cells with either NALM-6, Raji, or B cells in the presence of Vδ1 bispecifics and controls, as shown in (B), (C), and (D). (F-G) Effect of Vδ1-CD19 bispecifics on Vδ1 TCR surface expression in the presence of NALM-6 target cells (F) and healthy B cells (G), as determined by flow cytometry after 4 h of co-culture. (H) Bar graph representing the maximum percentage of TCR downregulation as shown in (F) and (G) at the highest concentration (3 μg / ml). (I-K) Effect of Vδ1-CD19 bispecifics on CD107a upregulation on the Vδ1 cell surface in the presence of NALM-6 target cells (I) and healthy B cells (J), as determined by flow cytometry after 4 h of co-culture. All data are shown as mean ± standard deviation and are representative of n = 3. Blinatumomab (CD3-CD19 bispecific (BiTE)) was included as a control in all assays. [Figure 50B]Vδ1-CD19 bispecific T cell engagers enhance CD19+ target cytotoxicity and γδ T cell activation while sparing healthy CD19+ B cells. (A) CD19 expression on cancerous NALM-6 and Raji cells, as well as primary B cells and Vδ1 γδ T cells, as determined by flow cytometry. (B-D) Effect of parental (ADT1-4) and affinity-matured (ADT1-4-2) Vδ1-CD19 bispecifics on NALM-6 cells (B), Raji cells (C), and B cell cytotoxicity (D). Antibodies were titrated over 12 h in the presence of Vδ1 γδ T cells at a 1:1 E:T ratio. The percentage of viable cells was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of Vδ1 γδ T cells. (E) Bar graph representing the percentage of viable cells after 12 h of co-culture of Vδ1 γδ T cells with either NALM-6, Raji, or B cells in the presence of Vδ1 bispecifics and controls, as shown in (B), (C), and (D). (F-G) Effect of Vδ1-CD19 bispecifics on Vδ1 TCR surface expression in the presence of NALM-6 target cells (F) and healthy B cells (G), as determined by flow cytometry after 4 h of co-culture. (H) Bar graph representing the maximum percentage of TCR downregulation as shown in (F) and (G) at the highest concentration (3 μg / ml). (I-K) Effect of Vδ1-CD19 bispecifics on CD107a upregulation on the Vδ1 cell surface in the presence of NALM-6 target cells (I) and healthy B cells (J), as determined by flow cytometry after 4 h of co-culture. All data are shown as mean ± standard deviation and are representative of n = 3. Blinatumomab (CD3-CD19 bispecific (BiTE)) was included as a control in all assays. [Figure 50C]Vδ1-CD19 bispecific T cell engagers enhance CD19+ target cytotoxicity and γδ T cell activation while sparing healthy CD19+ B cells. (A) CD19 expression on cancerous NALM-6 and Raji cells, as well as primary B cells and Vδ1 γδ T cells, as determined by flow cytometry. (B-D) Effect of parental (ADT1-4) and affinity-matured (ADT1-4-2) Vδ1-CD19 bispecifics on NALM-6 cells (B), Raji cells (C), and B cell cytotoxicity (D). Antibodies were titrated over 12 h in the presence of Vδ1 γδ T cells at a 1:1 E:T ratio. The percentage of viable cells was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of Vδ1 γδ T cells. (E) Bar graph representing the percentage of viable cells after 12 h of co-culture of Vδ1 γδ T cells with either NALM-6, Raji, or B cells in the presence of Vδ1 bispecifics and controls, as shown in (B), (C), and (D). (F-G) Effect of Vδ1-CD19 bispecifics on Vδ1 TCR surface expression in the presence of NALM-6 target cells (F) and healthy B cells (G), as determined by flow cytometry after 4 h of co-culture. (H) Bar graph representing the maximum percentage of TCR downregulation as shown in (F) and (G) at the highest concentration (3 μg / ml). (I-K) Effect of Vδ1-CD19 bispecifics on CD107a upregulation on the Vδ1 cell surface in the presence of NALM-6 target cells (I) and healthy B cells (J), as determined by flow cytometry after 4 h of co-culture. All data are shown as mean ± standard deviation and are representative of n = 3. Blinatumomab (CD3-CD19 bispecific (BiTE)) was included as a control in all assays. [Figure 50D]Vδ1-CD19 bispecific T cell engagers enhance CD19+ target cytotoxicity and γδ T cell activation while sparing healthy CD19+ B cells. (A) CD19 expression on cancerous NALM-6 and Raji cells, as well as primary B cells and Vδ1 γδ T cells, as determined by flow cytometry. (B-D) Effect of parental (ADT1-4) and affinity-matured (ADT1-4-2) Vδ1-CD19 bispecifics on NALM-6 cells (B), Raji cells (C), and B cell cytotoxicity (D). Antibodies were titrated over 12 h in the presence of Vδ1 γδ T cells at a 1:1 E:T ratio. The percentage of viable cells was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of Vδ1 γδ T cells. (E) Bar graph representing the percentage of viable cells after 12 h of co-culture of Vδ1 γδ T cells with either NALM-6, Raji, or B cells in the presence of Vδ1 bispecifics and controls, as shown in (B), (C), and (D). (F-G) Effect of Vδ1-CD19 bispecifics on Vδ1 TCR surface expression in the presence of NALM-6 target cells (F) and healthy B cells (G), as determined by flow cytometry after 4 h of co-culture. (H) Bar graph representing the maximum percentage of TCR downregulation as shown in (F) and (G) at the highest concentration (3 μg / ml). (I-K) Effect of Vδ1-CD19 bispecifics on CD107a upregulation on the Vδ1 cell surface in the presence of NALM-6 target cells (I) and healthy B cells (J), as determined by flow cytometry after 4 h of co-culture. All data are shown as mean ± standard deviation and are representative of n = 3. Blinatumomab (CD3-CD19 bispecific (BiTE)) was included as a control in all assays. [Figure 50E]Vδ1-CD19 bispecific T cell engagers enhance CD19+ target cytotoxicity and γδ T cell activation while sparing healthy CD19+ B cells. (A) CD19 expression on cancerous NALM-6 and Raji cells, as well as primary B cells and Vδ1 γδ T cells, as determined by flow cytometry. (B-D) Effect of parental (ADT1-4) and affinity-matured (ADT1-4-2) Vδ1-CD19 bispecifics on NALM-6 cells (B), Raji cells (C), and B cell cytotoxicity (D). Antibodies were titrated over 12 h in the presence of Vδ1 γδ T cells at a 1:1 E:T ratio. The percentage of viable cells was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of Vδ1 γδ T cells. (E) Bar graph representing the percentage of viable cells after 12 h of co-culture of Vδ1 γδ T cells with either NALM-6, Raji, or B cells in the presence of Vδ1 bispecifics and controls, as shown in (B), (C), and (D). (F-G) Effect of Vδ1-CD19 bispecifics on Vδ1 TCR surface expression in the presence of NALM-6 target cells (F) and healthy B cells (G), as determined by flow cytometry after 4 h of co-culture. (H) Bar graph representing the maximum percentage of TCR downregulation as shown in (F) and (G) at the highest concentration (3 μg / ml). (I-K) Effect of Vδ1-CD19 bispecifics on CD107a upregulation on the Vδ1 cell surface in the presence of NALM-6 target cells (I) and healthy B cells (J), as determined by flow cytometry after 4 h of co-culture. All data are shown as mean ± standard deviation and are representative of n = 3. Blinatumomab (CD3-CD19 bispecific (BiTE)) was included as a control in all assays. [Figure 50F]Vδ1-CD19 bispecific T cell engagers enhance CD19+ target cytotoxicity and γδ T cell activation while sparing healthy CD19+ B cells. (A) CD19 expression on cancerous NALM-6 and Raji cells, as well as primary B cells and Vδ1 γδ T cells, as determined by flow cytometry. (B-D) Effect of parental (ADT1-4) and affinity-matured (ADT1-4-2) Vδ1-CD19 bispecifics on NALM-6 cells (B), Raji cells (C), and B cell cytotoxicity (D). Antibodies were titrated over 12 h in the presence of Vδ1 γδ T cells at a 1:1 E:T ratio. The percentage of viable cells was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of Vδ1 γδ T cells. (E) Bar graph representing the percentage of viable cells after 12 h of co-culture of Vδ1 γδ T cells with either NALM-6, Raji, or B cells in the presence of Vδ1 bispecifics and controls, as shown in (B), (C), and (D). (F-G) Effect of Vδ1-CD19 bispecifics on Vδ1 TCR surface expression in the presence of NALM-6 target cells (F) and healthy B cells (G), as determined by flow cytometry after 4 h of co-culture. (H) Bar graph representing the maximum percentage of TCR downregulation as shown in (F) and (G) at the highest concentration (3 μg / ml). (I-K) Effect of Vδ1-CD19 bispecifics on CD107a upregulation on the Vδ1 cell surface in the presence of NALM-6 target cells (I) and healthy B cells (J), as determined by flow cytometry after 4 h of co-culture. All data are shown as mean ± standard deviation and are representative of n = 3. Blinatumomab (CD3-CD19 bispecific (BiTE)) was included as a control in all assays. [Figure 50G]Vδ1-CD19 bispecific T cell engagers enhance CD19+ target cytotoxicity and γδ T cell activation while sparing healthy CD19+ B cells. (A) CD19 expression on cancerous NALM-6 and Raji cells, as well as primary B cells and Vδ1 γδ T cells, as determined by flow cytometry. (B-D) Effect of parental (ADT1-4) and affinity-matured (ADT1-4-2) Vδ1-CD19 bispecifics on NALM-6 cells (B), Raji cells (C), and B cell cytotoxicity (D). Antibodies were titrated over 12 h in the presence of Vδ1 γδ T cells at a 1:1 E:T ratio. The percentage of viable cells was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of Vδ1 γδ T cells. (E) Bar graph representing the percentage of viable cells after 12 h of co-culture of Vδ1 γδ T cells with either NALM-6, Raji, or B cells in the presence of Vδ1 bispecifics and controls, as shown in (B), (C), and (D). (F-G) Effect of Vδ1-CD19 bispecifics on Vδ1 TCR surface expression in the presence of NALM-6 target cells (F) and healthy B cells (G), as determined by flow cytometry after 4 h of co-culture. (H) Bar graph representing the maximum percentage of TCR downregulation as shown in (F) and (G) at the highest concentration (3 μg / ml). (I-K) Effect of Vδ1-CD19 bispecifics on CD107a upregulation on the Vδ1 cell surface in the presence of NALM-6 target cells (I) and healthy B cells (J), as determined by flow cytometry after 4 h of co-culture. All data are shown as mean ± standard deviation and are representative of n = 3. Blinatumomab (CD3-CD19 bispecific (BiTE)) was included as a control in all assays. [Figure 50H]Vδ1-CD19 bispecific T cell engagers enhance CD19+ target cytotoxicity and γδ T cell activation while sparing healthy CD19+ B cells. (A) CD19 expression on cancerous NALM-6 and Raji cells, as well as primary B cells and Vδ1 γδ T cells, as determined by flow cytometry. (B-D) Effect of parental (ADT1-4) and affinity-matured (ADT1-4-2) Vδ1-CD19 bispecifics on NALM-6 cells (B), Raji cells (C), and B cell cytotoxicity (D). Antibodies were titrated over 12 h in the presence of Vδ1 γδ T cells at a 1:1 E:T ratio. The percentage of viable cells was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of Vδ1 γδ T cells. (E) Bar graph representing the percentage of viable cells after 12 h of co-culture of Vδ1 γδ T cells with either NALM-6, Raji, or B cells in the presence of Vδ1 bispecifics and controls, as shown in (B), (C), and (D). (F-G) Effect of Vδ1-CD19 bispecifics on Vδ1 TCR surface expression in the presence of NALM-6 target cells (F) and healthy B cells (G), as determined by flow cytometry after 4 h of co-culture. (H) Bar graph representing the maximum percentage of TCR downregulation as shown in (F) and (G) at the highest concentration (3 μg / ml). (I-K) Effect of Vδ1-CD19 bispecifics on CD107a upregulation on the Vδ1 cell surface in the presence of NALM-6 target cells (I) and healthy B cells (J), as determined by flow cytometry after 4 h of co-culture. All data are shown as mean ± standard deviation and are representative of n = 3. Blinatumomab (CD3-CD19 bispecific (BiTE)) was included as a control in all assays. [Figure 50I]Vδ1-CD19 bispecific T cell engagers enhance CD19+ target cytotoxicity and γδ T cell activation while sparing healthy CD19+ B cells. (A) CD19 expression on cancerous NALM-6 and Raji cells, as well as primary B cells and Vδ1 γδ T cells, as determined by flow cytometry. (B-D) Effect of parental (ADT1-4) and affinity-matured (ADT1-4-2) Vδ1-CD19 bispecifics on NALM-6 cells (B), Raji cells (C), and B cell cytotoxicity (D). Antibodies were titrated over 12 h in the presence of Vδ1 γδ T cells at a 1:1 E:T ratio. The percentage of viable cells was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of Vδ1 γδ T cells. (E) Bar graph representing the percentage of viable cells after 12 h of co-culture of Vδ1 γδ T cells with either NALM-6, Raji, or B cells in the presence of Vδ1 bispecifics and controls, as shown in (B), (C), and (D). (F-G) Effect of Vδ1-CD19 bispecifics on Vδ1 TCR surface expression in the presence of NALM-6 target cells (F) and healthy B cells (G), as determined by flow cytometry after 4 h of co-culture. (H) Bar graph representing the maximum percentage of TCR downregulation as shown in (F) and (G) at the highest concentration (3 μg / ml). (I-K) Effect of Vδ1-CD19 bispecifics on CD107a upregulation on the Vδ1 cell surface in the presence of NALM-6 target cells (I) and healthy B cells (J), as determined by flow cytometry after 4 h of co-culture. All data are shown as mean ± standard deviation and are representative of n = 3. Blinatumomab (CD3-CD19 bispecific (BiTE)) was included as a control in all assays. [Figure 50J]Vδ1-CD19 bispecific T cell engagers enhance CD19+ target cytotoxicity and γδ T cell activation while sparing healthy CD19+ B cells. (A) CD19 expression on cancerous NALM-6 and Raji cells, as well as primary B cells and Vδ1 γδ T cells, as determined by flow cytometry. (B-D) Effect of parental (ADT1-4) and affinity-matured (ADT1-4-2) Vδ1-CD19 bispecifics on NALM-6 cells (B), Raji cells (C), and B cell cytotoxicity (D). Antibodies were titrated over 12 h in the presence of Vδ1 γδ T cells at a 1:1 E:T ratio. The percentage of viable cells was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of Vδ1 γδ T cells. (E) Bar graph representing the percentage of viable cells after 12 h of co-culture of Vδ1 γδ T cells with either NALM-6, Raji, or B cells in the presence of Vδ1 bispecifics and controls, as shown in (B), (C), and (D). (F-G) Effect of Vδ1-CD19 bispecifics on Vδ1 TCR surface expression in the presence of NALM-6 target cells (F) and healthy B cells (G), as determined by flow cytometry after 4 h of co-culture. (H) Bar graph representing the maximum percentage of TCR downregulation as shown in (F) and (G) at the highest concentration (3 μg / ml). (I-K) Effect of Vδ1-CD19 bispecifics on CD107a upregulation on the Vδ1 cell surface in the presence of NALM-6 target cells (I) and healthy B cells (J), as determined by flow cytometry after 4 h of co-culture. All data are shown as mean ± standard deviation and are representative of n = 3. Blinatumomab (CD3-CD19 bispecific (BiTE)) was included as a control in all assays. [Figure 50K]Vδ1-CD19 bispecific T cell engagers enhance CD19+ target cytotoxicity and γδ T cell activation while sparing healthy CD19+ B cells. (A) CD19 expression on cancerous NALM-6 and Raji cells, as well as primary B cells and Vδ1 γδ T cells, as determined by flow cytometry. (B-D) Effect of parental (ADT1-4) and affinity-matured (ADT1-4-2) Vδ1-CD19 bispecifics on NALM-6 cells (B), Raji cells (C), and B cell cytotoxicity (D). Antibodies were titrated over 12 h in the presence of Vδ1 γδ T cells at a 1:1 E:T ratio. The percentage of viable cells was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of Vδ1 γδ T cells. (E) Bar graph representing the percentage of viable cells after 12 h of co-culture of Vδ1 γδ T cells with either NALM-6, Raji, or B cells in the presence of Vδ1 bispecifics and controls, as shown in (B), (C), and (D). (F-G) Effect of Vδ1-CD19 bispecifics on Vδ1 TCR surface expression in the presence of NALM-6 target cells (F) and healthy B cells (G), as determined by flow cytometry after 4 h of co-culture. (H) Bar graph representing the maximum percentage of TCR downregulation as shown in (F) and (G) at the highest concentration (3 μg / ml). (I-K) Effect of Vδ1-CD19 bispecifics on CD107a upregulation on the Vδ1 cell surface in the presence of NALM-6 target cells (I) and healthy B cells (J), as determined by flow cytometry after 4 h of co-culture. All data are shown as mean ± standard deviation and are representative of n = 3. Blinatumomab (CD3-CD19 bispecific (BiTE)) was included as a control in all assays. [Figure 51A]Affinity-matured V51 clones in a bispecific format bind to Her2+ target cells and show enhanced binding to V51 γδ T cells and enhanced cytotoxicity of Her2+ target cells. (A) Cell surface expression of Her2 and V51 on breast cancer cell lines and V51 γδ T cells (B). (C-F) Binding of Vδ1-Her2 bispecific antibody and Her2 mAb control (trastuzumab) to Her2+ (SK-BR-3 (C), BT-474 (D)), Her2- (MDA-MD-231 (E)) and Vδ1+ cells (F). (G-I) Percent viable cells remaining after 24 h of co-culture with Vδ1 γδ T cells and SK-BR-3 cells (G), BT-474 (H) and MDA-MB-231 cells (I) at a 1:1 E:T ratio in the presence of Vδ1-Her2 bispecific antibody. (J) Bar graph representing the percent increase in cytotoxicity of Vδ1 γδ T cells Vδ1-Her2 bispecific antibody after 24 h. [Figure 51B] Affinity-matured V51 clones in a bispecific format bind to Her2+ target cells and show enhanced binding to V51 γδ T cells and enhanced cytotoxicity of Her2+ target cells. (A) Cell surface expression of Her2 and V51 on breast cancer cell lines and V51 γδ T cells (B). (C-F) Binding of Vδ1-Her2 bispecific antibody and Her2 mAb control (trastuzumab) to Her2+ (SK-BR-3 (C), BT-474 (D)), Her2- (MDA-MD-231 (E)) and Vδ1+ cells (F). (G-I) Percent viable cells remaining after 24 h of co-culture with Vδ1 γδ T cells and SK-BR-3 cells (G), BT-474 (H) and MDA-MB-231 cells (I) at a 1:1 E:T ratio in the presence of Vδ1-Her2 bispecific antibody. (J) Bar graph representing the percent increase in cytotoxicity of Vδ1 γδ T cells Vδ1-Her2 bispecific antibody after 24 h. [Figure 51C]Affinity-matured V51 clones in a bispecific format bind to Her2+ target cells and show enhanced binding to V51 γδ T cells and enhanced cytotoxicity of Her2+ target cells. (A) Cell surface expression of Her2 and V51 on breast cancer cell lines and V51 γδ T cells (B). (C-F) Binding of Vδ1-Her2 bispecific antibody and Her2 mAb control (trastuzumab) to Her2+ (SK-BR-3 (C), BT-474 (D)), Her2- (MDA-MD-231 (E)) and Vδ1+ cells (F). (G-I) Percent viable cells remaining after 24 h of co-culture with Vδ1 γδ T cells and SK-BR-3 cells (G), BT-474 (H) and MDA-MB-231 cells (I) at a 1:1 E:T ratio in the presence of Vδ1-Her2 bispecific antibody. (J) Bar graph representing the percent increase in cytotoxicity of Vδ1 γδ T cells Vδ1-Her2 bispecific antibody after 24 h. [Figure 51D] Affinity-matured V51 clones in a bispecific format bind to Her2+ target cells and show enhanced binding to V51 γδ T cells and enhanced cytotoxicity of Her2+ target cells. (A) Cell surface expression of Her2 and V51 on breast cancer cell lines and V51 γδ T cells (B). (C-F) Binding of Vδ1-Her2 bispecific antibody and Her2 mAb control (trastuzumab) to Her2+ (SK-BR-3 (C), BT-474 (D)), Her2- (MDA-MD-231 (E)) and Vδ1+ cells (F). (G-I) Percent viable cells remaining after 24 h of co-culture with Vδ1 γδ T cells and SK-BR-3 cells (G), BT-474 (H) and MDA-MB-231 cells (I) at a 1:1 E:T ratio in the presence of Vδ1-Her2 bispecific antibody. (J) Bar graph representing the percent increase in cytotoxicity of Vδ1 γδ T cells Vδ1-Her2 bispecific antibody after 24 h. [Figure 51E]Affinity-matured V51 clones in a bispecific format bind to Her2+ target cells and show enhanced binding to V51 γδ T cells and enhanced cytotoxicity of Her2+ target cells. (A) Cell surface expression of Her2 and V51 on breast cancer cell lines and V51 γδ T cells (B). (C-F) Binding of Vδ1-Her2 bispecific antibody and Her2 mAb control (trastuzumab) to Her2+ (SK-BR-3 (C), BT-474 (D)), Her2- (MDA-MD-231 (E)) and Vδ1+ cells (F). (G-I) Percent viable cells remaining after 24 h of co-culture with Vδ1 γδ T cells and SK-BR-3 cells (G), BT-474 (H) and MDA-MB-231 cells (I) at a 1:1 E:T ratio in the presence of Vδ1-Her2 bispecific antibody. (J) Bar graph representing the percent increase in cytotoxicity of Vδ1 γδ T cells Vδ1-Her2 bispecific antibody after 24 h. [Figure 51F] Affinity-matured V51 clones in a bispecific format bind to Her2+ target cells and show enhanced binding to V51 γδ T cells and enhanced cytotoxicity of Her2+ target cells. (A) Cell surface expression of Her2 and V51 on breast cancer cell lines and V51 γδ T cells (B). (C-F) Binding of Vδ1-Her2 bispecific antibody and Her2 mAb control (trastuzumab) to Her2+ (SK-BR-3 (C), BT-474 (D)), Her2- (MDA-MD-231 (E)) and Vδ1+ cells (F). (G-I) Percent viable cells remaining after 24 h of co-culture with Vδ1 γδ T cells and SK-BR-3 cells (G), BT-474 (H) and MDA-MB-231 cells (I) at a 1:1 E:T ratio in the presence of Vδ1-Her2 bispecific antibody. (J) Bar graph representing the percent increase in cytotoxicity of Vδ1 γδ T cells Vδ1-Her2 bispecific antibody after 24 h. [Figure 51G]Affinity-matured V51 clones in a bispecific format bind to Her2+ target cells and show enhanced binding to V51 γδ T cells and enhanced cytotoxicity of Her2+ target cells. (A) Cell surface expression of Her2 and V51 on breast cancer cell lines and V51 γδ T cells (B). (C-F) Binding of Vδ1-Her2 bispecific antibody and Her2 mAb control (trastuzumab) to Her2+ (SK-BR-3 (C), BT-474 (D)), Her2- (MDA-MD-231 (E)) and Vδ1+ cells (F). (G-I) Percent viable cells remaining after 24 h of co-culture with Vδ1 γδ T cells and SK-BR-3 cells (G), BT-474 (H) and MDA-MB-231 cells (I) at a 1:1 E:T ratio in the presence of Vδ1-Her2 bispecific antibody. (J) Bar graph representing the percent increase in cytotoxicity of Vδ1 γδ T cells Vδ1-Her2 bispecific antibody after 24 h. [Figure 51H] Affinity-matured V51 clones in a bispecific format bind to Her2+ target cells and show enhanced binding to V51 γδ T cells and enhanced cytotoxicity of Her2+ target cells. (A) Cell surface expression of Her2 and V51 on breast cancer cell lines and V51 γδ T cells (B). (C-F) Binding of Vδ1-Her2 bispecific antibody and Her2 mAb control (trastuzumab) to Her2+ (SK-BR-3 (C), BT-474 (D)), Her2- (MDA-MD-231 (E)) and Vδ1+ cells (F). (G-I) Percent viable cells remaining after 24 h of co-culture with Vδ1 γδ T cells and SK-BR-3 cells (G), BT-474 (H) and MDA-MB-231 cells (I) at a 1:1 E:T ratio in the presence of Vδ1-Her2 bispecific antibody. (J) Bar graph representing the percent increase in cytotoxicity of Vδ1 γδ T cells Vδ1-Her2 bispecific antibody after 24 h. [Figure 51I]Affinity-matured V51 clones in a bispecific format bind to Her2+ target cells and show enhanced binding to V51 γδ T cells and enhanced cytotoxicity of Her2+ target cells. (A) Cell surface expression of Her2 and V51 on breast cancer cell lines and V51 γδ T cells (B). (C-F) Binding of Vδ1-Her2 bispecific antibody and Her2 mAb control (trastuzumab) to Her2+ (SK-BR-3 (C), BT-474 (D)), Her2- (MDA-MD-231 (E)) and Vδ1+ cells (F). (G-I) Percent viable cells remaining after 24 h of co-culture with Vδ1 γδ T cells and SK-BR-3 cells (G), BT-474 (H) and MDA-MB-231 cells (I) at a 1:1 E:T ratio in the presence of Vδ1-Her2 bispecific antibody. (J) Bar graph representing the percent increase in cytotoxicity of Vδ1 γδ T cells Vδ1-Her2 bispecific antibody after 24 h. [Figure 51J] Affinity-matured V51 clones in a bispecific format bind to Her2+ target cells and show enhanced binding to V51 γδ T cells and enhanced cytotoxicity of Her2+ target cells. (A) Cell surface expression of Her2 and V51 on breast cancer cell lines and V51 γδ T cells (B). (C-F) Binding of Vδ1-Her2 bispecific antibody and Her2 mAb control (trastuzumab) to Her2+ (SK-BR-3 (C), BT-474 (D)), Her2- (MDA-MD-231 (E)) and Vδ1+ cells (F). (G-I) Percent viable cells remaining after 24 h of co-culture with Vδ1 γδ T cells and SK-BR-3 cells (G), BT-474 (H) and MDA-MB-231 cells (I) at a 1:1 E:T ratio in the presence of Vδ1-Her2 bispecific antibody. (J) Bar graph representing the percent increase in cytotoxicity of Vδ1 γδ T cells Vδ1-Her2 bispecific antibody after 24 h. [Figure 52A]The V51 / EGFR bispecific antibody exhibits high affinity binding to human EGFR and comparable human V51 binding affinity to its parent mAb. (A, B) Surface plasmon resonance (SPR) analysis was performed with the V51 / EGFR bispecific variants to assess binding to human V51 (A) and human EGFR antigen (B). For comparison purposes, the parent mAb, cetuximab, and a negative control mAb were included. [Figure 52B] The V51 / EGFR bispecific antibody exhibits high affinity binding to human EGFR and comparable human V51 binding affinity to its parent mAb. (A, B) Surface plasmon resonance (SPR) analysis was performed with the V51 / EGFR bispecific variants to assess binding to human V51 (A) and human EGFR antigen (B). For comparison purposes, the parent mAb, cetuximab, and a negative control mAb were included. [Figure 53A] Vδ1 / EGFR bispecific antibodies bind to EGFR+ A431 target cells and Vδ1γδ T cells. (A) Cell surface expression of EGFR and Vδ1 on the A431 cell line and primary Vδ1γδ T cells. (B) Binding levels of Vδ1 / EGFR bispecific antibodies to A431 cell line or primary Vδ1γδ T cells. Target cells were stained with various concentrations of antibody followed by staining with a fluorescent anti-human IgG detection antibody. All incubation steps were performed at 4°C, and mAb binding was determined by measuring median fluorescence levels using flow cytometry. Logarithmic 4-parameter dose-response curve fitting was performed using GraphPad Prism 9. [Figure 53B] Vδ1 / EGFR bispecific antibodies bind to EGFR+ A431 target cells and Vδ1γδ T cells. (A) Cell surface expression of EGFR and Vδ1 on the A431 cell line and primary Vδ1γδ T cells. (B) Binding levels of Vδ1 / EGFR bispecific antibodies to A431 cell line or primary Vδ1γδ T cells. Target cells were stained with various concentrations of antibody followed by staining with a fluorescent anti-human IgG detection antibody. All incubation steps were performed at 4°C, and mAb binding was determined by measuring median fluorescence levels using flow cytometry. Logarithmic 4-parameter dose-response curve fitting was performed using GraphPad Prism 9. [Figure 54A] Vδ1 / EGFR bispecific antibodies induce activation and degranulation of EGFR-specific T cells, resulting in increased γδ T cell-mediated cytotoxicity of A431 target cells. (A) Cell surface expression of γδ TCR on primary Vδ1 γδ T cells after 24 h of culture with bispecific antibodies in the presence or absence of A431 cells. (B, C) Number of viable A431 cells (B) and activation status of primary Vδ1 γδ T cells after 24 h of coculture at a 1:1 ratio with various antibody concentrations. Viability was measured using a viability dye, and activation status was measured using a CD25 antibody. (D) Degranulation of primary Vδ1 γδ T cells after 4 h of coculture with A431 cells at a 1:1 ratio with various antibody concentrations. Degranulation was determined by adding a fluorophore-conjugated anti-CD107α antibody directly to the cell-antibody mix at the start of coculture. (E) Number of viable A431 cells after 24 h of co-culture with 10 pM antibody and varying amounts of primary Vδ1γδT cells. (A-E) In all cases, fluorescence was determined using flow cytometry to measure median fluorescence levels. Logarithmic 4-parameter dose-response curve fitting was performed using GraphPad Prism 9. Data are presented as the mean ± SD of two biological replicates. [Figure 54B]Vδ1 / EGFR bispecific antibodies induce activation and degranulation of EGFR-specific T cells, resulting in increased γδ T cell-mediated cytotoxicity of A431 target cells. (A) Cell surface expression of γδ TCR on primary Vδ1 γδ T cells after 24 h of culture with bispecific antibodies in the presence or absence of A431 cells. (B, C) Number of viable A431 cells (B) and activation status of primary Vδ1 γδ T cells after 24 h of coculture at a 1:1 ratio with various antibody concentrations. Viability was measured using a viability dye, and activation status was measured using a CD25 antibody. (D) Degranulation of primary Vδ1 γδ T cells after 4 h of coculture with A431 cells at a 1:1 ratio with various antibody concentrations. Degranulation was determined by adding a fluorophore-conjugated anti-CD107α antibody directly to the cell-antibody mix at the start of coculture. (E) Number of viable A431 cells after 24 h of co-culture with 10 pM antibody and varying amounts of primary Vδ1γδT cells. (A-E) In all cases, fluorescence was determined using flow cytometry to measure median fluorescence levels. Logarithmic 4-parameter dose-response curve fitting was performed using GraphPad Prism 9. Data are presented as the mean ± SD of two biological replicates. [Figure 54C]Vδ1 / EGFR bispecific antibodies induce activation and degranulation of EGFR-specific T cells, resulting in increased γδ T cell-mediated cytotoxicity of A431 target cells. (A) Cell surface expression of γδ TCR on primary Vδ1 γδ T cells after 24 h of culture with bispecific antibodies in the presence or absence of A431 cells. (B, C) Number of viable A431 cells (B) and activation status of primary Vδ1 γδ T cells after 24 h of coculture at a 1:1 ratio with various antibody concentrations. Viability was measured using a viability dye, and activation status was measured using a CD25 antibody. (D) Degranulation of primary Vδ1 γδ T cells after 4 h of coculture with A431 cells at a 1:1 ratio with various antibody concentrations. Degranulation was determined by adding a fluorophore-conjugated anti-CD107α antibody directly to the cell-antibody mix at the start of coculture. (E) Number of viable A431 cells after 24 h of co-culture with 10 pM antibody and varying amounts of primary Vδ1γδT cells. (A-E) In all cases, fluorescence was determined using flow cytometry to measure median fluorescence levels. Logarithmic 4-parameter dose-response curve fitting was performed using GraphPad Prism 9. Data are presented as the mean ± SD of two biological replicates. [Figure 54D]Vδ1 / EGFR bispecific antibodies induce activation and degranulation of EGFR-specific T cells, resulting in increased γδ T cell-mediated cytotoxicity of A431 target cells. (A) Cell surface expression of γδ TCR on primary Vδ1 γδ T cells after 24 h of culture with bispecific antibodies in the presence or absence of A431 cells. (B, C) Number of viable A431 cells (B) and activation status of primary Vδ1 γδ T cells after 24 h of coculture at a 1:1 ratio with various antibody concentrations. Viability was measured using a viability dye, and activation status was measured using a CD25 antibody. (D) Degranulation of primary Vδ1 γδ T cells after 4 h of coculture with A431 cells at a 1:1 ratio with various antibody concentrations. Degranulation was determined by adding a fluorophore-conjugated anti-CD107α antibody directly to the cell-antibody mix at the start of coculture. (E) Number of viable A431 cells after 24 h of co-culture with 10 pM antibody and varying amounts of primary Vδ1γδT cells. (A-E) In all cases, fluorescence was determined using flow cytometry to measure median fluorescence levels. Logarithmic 4-parameter dose-response curve fitting was performed using GraphPad Prism 9. Data are presented as the mean ± SD of two biological replicates. [Figure 54E]Vδ1 / EGFR bispecific antibodies induce activation and degranulation of EGFR-specific T cells, resulting in increased γδ T cell-mediated cytotoxicity of A431 target cells. (A) Cell surface expression of γδ TCR on primary Vδ1 γδ T cells after 24 h of culture with bispecific antibodies in the presence or absence of A431 cells. (B, C) Number of viable A431 cells (B) and activation status of primary Vδ1 γδ T cells after 24 h of coculture at a 1:1 ratio with various antibody concentrations. Viability was measured using a viability dye, and activation status was measured using a CD25 antibody. (D) Degranulation of primary Vδ1 γδ T cells after 4 h of coculture with A431 cells at a 1:1 ratio with various antibody concentrations. Degranulation was determined by adding a fluorophore-conjugated anti-CD107α antibody directly to the cell-antibody mix at the start of coculture. (E) Number of viable A431 cells after 24 h of co-culture with 10 pM antibody and varying amounts of primary Vδ1γδT cells. (A-E) In all cases, fluorescence was determined using flow cytometry to measure median fluorescence levels. Logarithmic 4-parameter dose-response curve fitting was performed using GraphPad Prism 9. Data are presented as the mean ± SD of two biological replicates. [Figure 55A] Further evidence of non-depletion and CD3 downregulation in both blood-derived and tumor-associated V51 T cells is shown. (A) v51 TCR MFI upon antibody stimulation is shown as a measure of mAb target engagement on blood-derived V51 T cells. (B) MFI of CD3 expression on positively gated blood-derived v51 cells is shown. Stimulation with v51 antibodies engaged v51 cells and resulted in downregulation of both v51 and CD3 on v51 cells. (C, D, and E) Activating and non-depleting effects conferred on tumor-associated V51 T cells by exemplary anti-V51 antibodies of the invention are shown. [Figure 55B]Further evidence of non-depletion and CD3 downregulation in both blood-derived and tumor-associated V51 T cells is shown. (A) v51 TCR MFI upon antibody stimulation is shown as a measure of mAb target engagement on blood-derived V51 T cells. (B) MFI of CD3 expression on positively gated blood-derived v51 cells is shown. Stimulation with v51 antibodies engaged v51 cells and resulted in downregulation of both v51 and CD3 on v51 cells. (C, D, and E) Activating and non-depleting effects conferred on tumor-associated V51 T cells by exemplary anti-V51 antibodies of the invention are shown. [Figure 55C] Further evidence of non-depletion and CD3 downregulation in both blood-derived and tumor-associated V51 T cells is shown. (A) v51 TCR MFI upon antibody stimulation is shown as a measure of mAb target engagement on blood-derived V51 T cells. (B) MFI of CD3 expression on positively gated blood-derived v51 cells is shown. Stimulation with v51 antibodies engaged v51 cells and resulted in downregulation of both v51 and CD3 on v51 cells. (C, D, and E) Activating and non-depleting effects conferred on tumor-associated V51 T cells by exemplary anti-V51 antibodies of the invention are shown. [Figure 55D] Further evidence of non-depletion and CD3 downregulation in both blood-derived and tumor-associated V51 T cells is shown. (A) v51 TCR MFI upon antibody stimulation is shown as a measure of mAb target engagement on blood-derived V51 T cells. (B) MFI of CD3 expression on positively gated blood-derived v51 cells is shown. Stimulation with v51 antibodies engaged v51 cells and resulted in downregulation of both v51 and CD3 on v51 cells. (C, D, and E) Activating and non-depleting effects conferred on tumor-associated V51 T cells by exemplary anti-V51 antibodies of the invention are shown. [Figure 55E]Further evidence of non-depletion and CD3 downregulation in both blood-derived and tumor-associated V51 T cells is shown. (A) v51 TCR MFI upon antibody stimulation is shown as a measure of mAb target engagement on blood-derived V51 T cells. (B) MFI of CD3 expression on positively gated blood-derived v51 cells is shown. Stimulation with v51 antibodies engaged v51 cells and resulted in downregulation of both v51 and CD3 on v51 cells. (C, D, and E) Activating and non-depleting effects conferred on tumor-associated V51 T cells by exemplary anti-V51 antibodies of the invention are shown. [Figure 56A] V51 x FAPα bispecific antibodies enhance activation of V51 γδ T cells and lysis of FAPα+ fibroblasts. (A) Binding kinetics of anti-V51 (ADT-1-4-2), anti-FAPα monoclonal (based on sibrotuzumab), and anti-V51xFAPα (ADT-1-4-2xsibrotuzumab) bispecific antibodies for recombinant human V51 and FAPα as measured by surface plasmon resonance (SPR). (B, C) Binding of anti-V51 and anti-FAPα antibodies to FAPα+ fibroblasts (B) and V51 γδ T cells (C). (D, E) Effect of anti-V51 x FAPα bispecific antibodies and monoclonal controls on downregulation of V51 TCR in V51 γδ T cells in the absence (D) or presence (E) of FAPα+ fibroblasts. (F-G) Effect of anti-Vδ1 x FAPα bispecific antibody and monoclonal control on upregulation of CD107a in Vδ1γδ T cells in the absence (F) or presence (G) of FAPα+ fibroblasts. (H) Effect of anti-Vδ1 x FAPα bispecific antibody and monoclonal control on lysis of fibroblasts by Vδ1γδ T cells after 24 h of co-culture. Viable cell percentage was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of Vδ1γδ T cells. [Figure 56B]V51 x FAPα bispecific antibodies enhance activation of V51 γδ T cells and lysis of FAPα+ fibroblasts. (A) Binding kinetics of anti-V51 (ADT-1-4-2), anti-FAPα monoclonal (based on sibrotuzumab), and anti-V51xFAPα (ADT-1-4-2xsibrotuzumab) bispecific antibodies for recombinant human V51 and FAPα as measured by surface plasmon resonance (SPR). (B, C) Binding of anti-V51 and anti-FAPα antibodies to FAPα+ fibroblasts (B) and V51 γδ T cells (C). (D, E) Effect of anti-V51 x FAPα bispecific antibodies and monoclonal controls on downregulation of V51 TCR in V51 γδ T cells in the absence (D) or presence (E) of FAPα+ fibroblasts. (F-G) Effect of anti-Vδ1 x FAPα bispecific antibody and monoclonal control on upregulation of CD107a in Vδ1γδ T cells in the absence (F) or presence (G) of FAPα+ fibroblasts. (H) Effect of anti-Vδ1 x FAPα bispecific antibody and monoclonal control on lysis of fibroblasts by Vδ1γδ T cells after 24 h of co-culture. Viable cell percentage was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of Vδ1γδ T cells. [Figure 56C]V51 x FAPα bispecific antibodies enhance activation of V51 γδ T cells and lysis of FAPα+ fibroblasts. (A) Binding kinetics of anti-V51 (ADT-1-4-2), anti-FAPα monoclonal (based on sibrotuzumab), and anti-V51xFAPα (ADT-1-4-2xsibrotuzumab) bispecific antibodies for recombinant human V51 and FAPα as measured by surface plasmon resonance (SPR). (B, C) Binding of anti-V51 and anti-FAPα antibodies to FAPα+ fibroblasts (B) and V51 γδ T cells (C). (D, E) Effect of anti-V51 x FAPα bispecific antibodies and monoclonal controls on downregulation of V51 TCR in V51 γδ T cells in the absence (D) or presence (E) of FAPα+ fibroblasts. (F-G) Effect of anti-Vδ1 x FAPα bispecific antibody and monoclonal control on upregulation of CD107a in Vδ1γδ T cells in the absence (F) or presence (G) of FAPα+ fibroblasts. (H) Effect of anti-Vδ1 x FAPα bispecific antibody and monoclonal control on lysis of fibroblasts by Vδ1γδ T cells after 24 h of co-culture. Viable cell percentage was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of Vδ1γδ T cells. [Figure 56D]V51 x FAPα bispecific antibodies enhance activation of V51 γδ T cells and lysis of FAPα+ fibroblasts. (A) Binding kinetics of anti-V51 (ADT-1-4-2), anti-FAPα monoclonal (based on sibrotuzumab), and anti-V51xFAPα (ADT-1-4-2xsibrotuzumab) bispecific antibodies for recombinant human V51 and FAPα as measured by surface plasmon resonance (SPR). (B, C) Binding of anti-V51 and anti-FAPα antibodies to FAPα+ fibroblasts (B) and V51 γδ T cells (C). (D, E) Effect of anti-V51 x FAPα bispecific antibodies and monoclonal controls on downregulation of V51 TCR in V51 γδ T cells in the absence (D) or presence (E) of FAPα+ fibroblasts. (F-G) Effect of anti-Vδ1 x FAPα bispecific antibody and monoclonal control on upregulation of CD107a in Vδ1γδ T cells in the absence (F) or presence (G) of FAPα+ fibroblasts. (H) Effect of anti-Vδ1 x FAPα bispecific antibody and monoclonal control on lysis of fibroblasts by Vδ1γδ T cells after 24 h of co-culture. Viable cell percentage was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of Vδ1γδ T cells. [Figure 56E]V51 x FAPα bispecific antibodies enhance activation of V51 γδ T cells and lysis of FAPα+ fibroblasts. (A) Binding kinetics of anti-V51 (ADT-1-4-2), anti-FAPα monoclonal (based on sibrotuzumab), and anti-V51xFAPα (ADT-1-4-2xsibrotuzumab) bispecific antibodies for recombinant human V51 and FAPα as measured by surface plasmon resonance (SPR). (B, C) Binding of anti-V51 and anti-FAPα antibodies to FAPα+ fibroblasts (B) and V51 γδ T cells (C). (D, E) Effect of anti-V51 x FAPα bispecific antibodies and monoclonal controls on downregulation of V51 TCR in V51 γδ T cells in the absence (D) or presence (E) of FAPα+ fibroblasts. (F-G) Effect of anti-Vδ1 x FAPα bispecific antibody and monoclonal control on upregulation of CD107a in Vδ1γδ T cells in the absence (F) or presence (G) of FAPα+ fibroblasts. (H) Effect of anti-Vδ1 x FAPα bispecific antibody and monoclonal control on lysis of fibroblasts by Vδ1γδ T cells after 24 h of co-culture. Viable cell percentage was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of Vδ1γδ T cells. [Figure 56F]V51 x FAPα bispecific antibodies enhance activation of V51 γδ T cells and lysis of FAPα+ fibroblasts. (A) Binding kinetics of anti-V51 (ADT-1-4-2), anti-FAPα monoclonal (based on sibrotuzumab), and anti-V51xFAPα (ADT-1-4-2xsibrotuzumab) bispecific antibodies for recombinant human V51 and FAPα as measured by surface plasmon resonance (SPR). (B, C) Binding of anti-V51 and anti-FAPα antibodies to FAPα+ fibroblasts (B) and V51 γδ T cells (C). (D, E) Effect of anti-V51 x FAPα bispecific antibodies and monoclonal controls on downregulation of V51 TCR in V51 γδ T cells in the absence (D) or presence (E) of FAPα+ fibroblasts. (F-G) Effect of anti-Vδ1 x FAPα bispecific antibody and monoclonal control on upregulation of CD107a in Vδ1γδ T cells in the absence (F) or presence (G) of FAPα+ fibroblasts. (H) Effect of anti-Vδ1 x FAPα bispecific antibody and monoclonal control on lysis of fibroblasts by Vδ1γδ T cells after 24 h of co-culture. Viable cell percentage was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of Vδ1γδ T cells. [Figure 56G]V51 x FAPα bispecific antibodies enhance activation of V51 γδ T cells and lysis of FAPα+ fibroblasts. (A) Binding kinetics of anti-V51 (ADT-1-4-2), anti-FAPα monoclonal (based on sibrotuzumab), and anti-V51xFAPα (ADT-1-4-2xsibrotuzumab) bispecific antibodies for recombinant human V51 and FAPα as measured by surface plasmon resonance (SPR). (B, C) Binding of anti-V51 and anti-FAPα antibodies to FAPα+ fibroblasts (B) and V51 γδ T cells (C). (D, E) Effect of anti-V51 x FAPα bispecific antibodies and monoclonal controls on downregulation of V51 TCR in V51 γδ T cells in the absence (D) or presence (E) of FAPα+ fibroblasts. (F-G) Effect of anti-Vδ1 x FAPα bispecific antibody and monoclonal control on upregulation of CD107a in Vδ1γδ T cells in the absence (F) or presence (G) of FAPα+ fibroblasts. (H) Effect of anti-Vδ1 x FAPα bispecific antibody and monoclonal control on lysis of fibroblasts by Vδ1γδ T cells after 24 h of co-culture. Viable cell percentage was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of Vδ1γδ T cells. [Figure 56H]V51 x FAPα bispecific antibodies enhance activation of V51 γδ T cells and lysis of FAPα+ fibroblasts. (A) Binding kinetics of anti-V51 (ADT-1-4-2), anti-FAPα monoclonal (based on sibrotuzumab), and anti-V51xFAPα (ADT-1-4-2xsibrotuzumab) bispecific antibodies for recombinant human V51 and FAPα as measured by surface plasmon resonance (SPR). (B, C) Binding of anti-V51 and anti-FAPα antibodies to FAPα+ fibroblasts (B) and V51 γδ T cells (C). (D, E) Effect of anti-V51 x FAPα bispecific antibodies and monoclonal controls on downregulation of V51 TCR in V51 γδ T cells in the absence (D) or presence (E) of FAPα+ fibroblasts. (F-G) Effect of anti-Vδ1 x FAPα bispecific antibody and monoclonal control on upregulation of CD107a in Vδ1γδ T cells in the absence (F) or presence (G) of FAPα+ fibroblasts. (H) Effect of anti-Vδ1 x FAPα bispecific antibody and monoclonal control on lysis of fibroblasts by Vδ1γδ T cells after 24 h of co-culture. Viable cell percentage was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of Vδ1γδ T cells. [Figure 57A]V51 x MSLN bispecific antibodies enhance V51 γδ T cell activation and lysis of MSLN+ target cells. (A) Binding kinetics of anti-V51 (ADT-1-4-2), anti-MSLN monoclonal (based on the antibody disclosed in US Patent Application Publication No. 2014 / 0004121), and anti-V51 x MSLN (ADT1-4-2xMSLN) bispecific antibodies to recombinant human V51 and MSLN as determined by surface plasmon resonance (SPR). (B, C) Binding of anti-V51 and anti-MSLN antibodies to MSLN+ HeLa cells (B) and V51 γδ T cells (C). (D, E) Effect of anti-V51 x MSLN bispecific and monoclonal antibodies on downregulation of V51 TCR in V51 γδ T cells in the absence (D) or presence (E) of MSLN+ OVCAR-3 cells. (F, G) Effect of anti-V51 x MSLN bispecific antibody and monoclonal control on upregulation of CD107a in V51 γδ T cells in the absence (F) or presence (G) of MSLN + OVCAR-3 cells. (H) Effect of anti-V51 x MSLN bispecific antibody and monoclonal control on lysis of HeLa cells by V51 γδ T cells after 24 h of co-culture. Viable cell percentage was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of V51 γδ T cells. [Figure 57B]V51 x MSLN bispecific antibodies enhance V51 γδ T cell activation and lysis of MSLN+ target cells. (A) Binding kinetics of anti-V51 (ADT-1-4-2), anti-MSLN monoclonal (based on the antibody disclosed in US Patent Application Publication No. 2014 / 0004121), and anti-V51 x MSLN (ADT1-4-2xMSLN) bispecific antibodies to recombinant human V51 and MSLN as determined by surface plasmon resonance (SPR). (B, C) Binding of anti-V51 and anti-MSLN antibodies to MSLN+ HeLa cells (B) and V51 γδ T cells (C). (D, E) Effect of anti-V51 x MSLN bispecific and monoclonal antibodies on downregulation of V51 TCR in V51 γδ T cells in the absence (D) or presence (E) of MSLN+ OVCAR-3 cells. (F, G) Effect of anti-V51 x MSLN bispecific antibody and monoclonal control on upregulation of CD107a in V51 γδ T cells in the absence (F) or presence (G) of MSLN + OVCAR-3 cells. (H) Effect of anti-V51 x MSLN bispecific antibody and monoclonal control on lysis of HeLa cells by V51 γδ T cells after 24 h of co-culture. Viable cell percentage was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of V51 γδ T cells. [Figure 57C]V51 x MSLN bispecific antibodies enhance V51 γδ T cell activation and lysis of MSLN+ target cells. (A) Binding kinetics of anti-V51 (ADT-1-4-2), anti-MSLN monoclonal (based on the antibody disclosed in US Patent Application Publication No. 2014 / 0004121), and anti-V51 x MSLN (ADT1-4-2xMSLN) bispecific antibodies to recombinant human V51 and MSLN as determined by surface plasmon resonance (SPR). (B, C) Binding of anti-V51 and anti-MSLN antibodies to MSLN+ HeLa cells (B) and V51 γδ T cells (C). (D, E) Effect of anti-V51 x MSLN bispecific and monoclonal antibodies on downregulation of V51 TCR in V51 γδ T cells in the absence (D) or presence (E) of MSLN+ OVCAR-3 cells. (F, G) Effect of anti-V51 x MSLN bispecific antibody and monoclonal control on upregulation of CD107a in V51 γδ T cells in the absence (F) or presence (G) of MSLN + OVCAR-3 cells. (H) Effect of anti-V51 x MSLN bispecific antibody and monoclonal control on lysis of HeLa cells by V51 γδ T cells after 24 h of co-culture. Viable cell percentage was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of V51 γδ T cells. [Figure 57D]V51 x MSLN bispecific antibodies enhance V51 γδ T cell activation and lysis of MSLN+ target cells. (A) Binding kinetics of anti-V51 (ADT-1-4-2), anti-MSLN monoclonal (based on the antibody disclosed in US Patent Application Publication No. 2014 / 0004121), and anti-V51 x MSLN (ADT1-4-2xMSLN) bispecific antibodies to recombinant human V51 and MSLN as determined by surface plasmon resonance (SPR). (B, C) Binding of anti-V51 and anti-MSLN antibodies to MSLN+ HeLa cells (B) and V51 γδ T cells (C). (D, E) Effect of anti-V51 x MSLN bispecific and monoclonal antibodies on downregulation of V51 TCR in V51 γδ T cells in the absence (D) or presence (E) of MSLN+ OVCAR-3 cells. (F, G) Effect of anti-V51 x MSLN bispecific antibody and monoclonal control on upregulation of CD107a in V51 γδ T cells in the absence (F) or presence (G) of MSLN + OVCAR-3 cells. (H) Effect of anti-V51 x MSLN bispecific antibody and monoclonal control on lysis of HeLa cells by V51 γδ T cells after 24 h of co-culture. Viable cell percentage was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of V51 γδ T cells. [Figure 57E]V51 x MSLN bispecific antibodies enhance V51 γδ T cell activation and lysis of MSLN+ target cells. (A) Binding kinetics of anti-V51 (ADT-1-4-2), anti-MSLN monoclonal (based on the antibody disclosed in US Patent Application Publication No. 2014 / 0004121), and anti-V51 x MSLN (ADT1-4-2xMSLN) bispecific antibodies to recombinant human V51 and MSLN as determined by surface plasmon resonance (SPR). (B, C) Binding of anti-V51 and anti-MSLN antibodies to MSLN+ HeLa cells (B) and V51 γδ T cells (C). (D, E) Effect of anti-V51 x MSLN bispecific and monoclonal antibodies on downregulation of V51 TCR in V51 γδ T cells in the absence (D) or presence (E) of MSLN+ OVCAR-3 cells. (F, G) Effect of anti-V51 x MSLN bispecific antibody and monoclonal control on upregulation of CD107a in V51 γδ T cells in the absence (F) or presence (G) of MSLN + OVCAR-3 cells. (H) Effect of anti-V51 x MSLN bispecific antibody and monoclonal control on lysis of HeLa cells by V51 γδ T cells after 24 h of co-culture. Viable cell percentage was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of V51 γδ T cells. [Figure 57F]V51 x MSLN bispecific antibodies enhance V51 γδ T cell activation and lysis of MSLN+ target cells. (A) Binding kinetics of anti-V51 (ADT-1-4-2), anti-MSLN monoclonal (based on the antibody disclosed in US Patent Application Publication No. 2014 / 0004121), and anti-V51 x MSLN (ADT1-4-2xMSLN) bispecific antibodies to recombinant human V51 and MSLN as determined by surface plasmon resonance (SPR). (B, C) Binding of anti-V51 and anti-MSLN antibodies to MSLN+ HeLa cells (B) and V51 γδ T cells (C). (D, E) Effect of anti-V51 x MSLN bispecific and monoclonal antibodies on downregulation of V51 TCR in V51 γδ T cells in the absence (D) or presence (E) of MSLN+ OVCAR-3 cells. (F, G) Effect of anti-V51 x MSLN bispecific antibody and monoclonal control on upregulation of CD107a in V51 γδ T cells in the absence (F) or presence (G) of MSLN + OVCAR-3 cells. (H) Effect of anti-V51 x MSLN bispecific antibody and monoclonal control on lysis of HeLa cells by V51 γδ T cells after 24 h of co-culture. Viable cell percentage was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of V51 γδ T cells. [Figure 57G]V51 x MSLN bispecific antibodies enhance V51 γδ T cell activation and lysis of MSLN+ target cells. (A) Binding kinetics of anti-V51 (ADT-1-4-2), anti-MSLN monoclonal (based on the antibody disclosed in US Patent Application Publication No. 2014 / 0004121), and anti-V51 x MSLN (ADT1-4-2xMSLN) bispecific antibodies to recombinant human V51 and MSLN as determined by surface plasmon resonance (SPR). (B, C) Binding of anti-V51 and anti-MSLN antibodies to MSLN+ HeLa cells (B) and V51 γδ T cells (C). (D, E) Effect of anti-V51 x MSLN bispecific and monoclonal antibodies on downregulation of V51 TCR in V51 γδ T cells in the absence (D) or presence (E) of MSLN+ OVCAR-3 cells. (F, G) Effect of anti-V51 x MSLN bispecific antibody and monoclonal control on upregulation of CD107a in V51 γδ T cells in the absence (F) or presence (G) of MSLN + OVCAR-3 cells. (H) Effect of anti-V51 x MSLN bispecific antibody and monoclonal control on lysis of HeLa cells by V51 γδ T cells after 24 h of co-culture. Viable cell percentage was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of V51 γδ T cells. [Figure 57H]V51 x MSLN bispecific antibodies enhance V51 γδ T cell activation and lysis of MSLN+ target cells. (A) Binding kinetics of anti-V51 (ADT-1-4-2), anti-MSLN monoclonal (based on the antibody disclosed in US Patent Application Publication No. 2014 / 0004121), and anti-V51 x MSLN (ADT1-4-2xMSLN) bispecific antibodies to recombinant human V51 and MSLN as determined by surface plasmon resonance (SPR). (B, C) Binding of anti-V51 and anti-MSLN antibodies to MSLN+ HeLa cells (B) and V51 γδ T cells (C). (D, E) Effect of anti-V51 x MSLN bispecific and monoclonal antibodies on downregulation of V51 TCR in V51 γδ T cells in the absence (D) or presence (E) of MSLN+ OVCAR-3 cells. (F, G) Effect of anti-V51 x MSLN bispecific antibody and monoclonal control on upregulation of CD107a in V51 γδ T cells in the absence (F) or presence (G) of MSLN + OVCAR-3 cells. (H) Effect of anti-V51 x MSLN bispecific antibody and monoclonal control on lysis of HeLa cells by V51 γδ T cells after 24 h of co-culture. Viable cell percentage was calculated by high-content confocal microscopy and normalized to the number of viable cells in the absence of V51 γδ T cells. [Figure 58A]V51 x PD-1 bispecific antibodies enhance activation of V51 γδ T cells and inhibit checkpoint blockade of PD-1+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-PD-1 (pembrolizumab-based), anti-RSV IgG control x anti-PD-1, and anti-V51 x anti-PD-1 (ADT1-4-2 x pembrolizumab) bispecific antibodies binding to recombinant human V51 and PD-1. B) Dual binding of anti-V51 and anti-PD-1 bispecific antibodies to recombinant human PD-1 and V51 as determined by SPR. C) PD-1 expression on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-PD-1 antibodies to PD-1+ activated CD4 and CD8 T cells and V51 γδ T cells. E) Effect of anti-V51 x PD-1 bispecific antibody and monoclonal control on downregulation of V51 TCR in V51 γδ T cells in the absence or presence of PD-1+ CD4 T cells. F) EC50 of anti-V51 x PD-1 bispecific antibody on downregulation of V51 TCR in V51 γδ T cells in the presence or absence of PD-1+ CD4 T cells. G) Effect of V51 cross-linking anti-V51 x PD-1 bispecific antibody on activation of PD-1+ T cells. [Figure 58B]V51 x PD-1 bispecific antibodies enhance activation of V51 γδ T cells and inhibit checkpoint blockade of PD-1+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-PD-1 (pembrolizumab-based), anti-RSV IgG control x anti-PD-1, and anti-V51 x anti-PD-1 (ADT1-4-2 x pembrolizumab) bispecific antibodies binding to recombinant human V51 and PD-1. B) Dual binding of anti-V51 and anti-PD-1 bispecific antibodies to recombinant human PD-1 and V51 as determined by SPR. C) PD-1 expression on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-PD-1 antibodies to PD-1+ activated CD4 and CD8 T cells and V51 γδ T cells. E) Effect of anti-V51 x PD-1 bispecific antibody and monoclonal control on downregulation of V51 TCR in V51 γδ T cells in the absence or presence of PD-1+ CD4 T cells. F) EC50 of anti-V51 x PD-1 bispecific antibody on downregulation of V51 TCR in V51 γδ T cells in the presence or absence of PD-1+ CD4 T cells. G) Effect of V51 cross-linking anti-V51 x PD-1 bispecific antibody on activation of PD-1+ T cells. [Figure 58C]V51 x PD-1 bispecific antibodies enhance activation of V51 γδ T cells and inhibit checkpoint blockade of PD-1+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-PD-1 (pembrolizumab-based), anti-RSV IgG control x anti-PD-1, and anti-V51 x anti-PD-1 (ADT1-4-2 x pembrolizumab) bispecific antibodies binding to recombinant human V51 and PD-1. B) Dual binding of anti-V51 and anti-PD-1 bispecific antibodies to recombinant human PD-1 and V51 as determined by SPR. C) PD-1 expression on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-PD-1 antibodies to PD-1+ activated CD4 and CD8 T cells and V51 γδ T cells. E) Effect of anti-V51 x PD-1 bispecific antibody and monoclonal control on downregulation of V51 TCR in V51 γδ T cells in the absence or presence of PD-1+ CD4 T cells. F) EC50 of anti-V51 x PD-1 bispecific antibody on downregulation of V51 TCR in V51 γδ T cells in the presence or absence of PD-1+ CD4 T cells. G) Effect of V51 cross-linking anti-V51 x PD-1 bispecific antibody on activation of PD-1+ T cells. [Figure 58D]V51 x PD-1 bispecific antibodies enhance activation of V51 γδ T cells and inhibit checkpoint blockade of PD-1+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-PD-1 (pembrolizumab-based), anti-RSV IgG control x anti-PD-1, and anti-V51 x anti-PD-1 (ADT1-4-2 x pembrolizumab) bispecific antibodies binding to recombinant human V51 and PD-1. B) Dual binding of anti-V51 and anti-PD-1 bispecific antibodies to recombinant human PD-1 and V51 as determined by SPR. C) PD-1 expression on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-PD-1 antibodies to PD-1+ activated CD4 and CD8 T cells and V51 γδ T cells. E) Effect of anti-V51 x PD-1 bispecific antibody and monoclonal control on downregulation of V51 TCR in V51 γδ T cells in the absence or presence of PD-1+ CD4 T cells. F) EC50 of anti-V51 x PD-1 bispecific antibody on downregulation of V51 TCR in V51 γδ T cells in the presence or absence of PD-1+ CD4 T cells. G) Effect of V51 cross-linking anti-V51 x PD-1 bispecific antibody on activation of PD-1+ T cells. [Figure 58E]V51 x PD-1 bispecific antibodies enhance activation of V51 γδ T cells and inhibit checkpoint blockade of PD-1+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-PD-1 (pembrolizumab-based), anti-RSV IgG control x anti-PD-1, and anti-V51 x anti-PD-1 (ADT1-4-2 x pembrolizumab) bispecific antibodies binding to recombinant human V51 and PD-1. B) Dual binding of anti-V51 and anti-PD-1 bispecific antibodies to recombinant human PD-1 and V51 as determined by SPR. C) PD-1 expression on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-PD-1 antibodies to PD-1+ activated CD4 and CD8 T cells and V51 γδ T cells. E) Effect of anti-V51 x PD-1 bispecific antibody and monoclonal control on downregulation of V51 TCR in V51 γδ T cells in the absence or presence of PD-1+ CD4 T cells. F) EC50 of anti-V51 x PD-1 bispecific antibody on downregulation of V51 TCR in V51 γδ T cells in the presence or absence of PD-1+ CD4 T cells. G) Effect of V51 cross-linking anti-V51 x PD-1 bispecific antibody on activation of PD-1+ T cells. [Figure 58F]V51 x PD-1 bispecific antibodies enhance activation of V51 γδ T cells and inhibit checkpoint blockade of PD-1+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-PD-1 (pembrolizumab-based), anti-RSV IgG control x anti-PD-1, and anti-V51 x anti-PD-1 (ADT1-4-2 x pembrolizumab) bispecific antibodies binding to recombinant human V51 and PD-1. B) Dual binding of anti-V51 and anti-PD-1 bispecific antibodies to recombinant human PD-1 and V51 as determined by SPR. C) PD-1 expression on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-PD-1 antibodies to PD-1+ activated CD4 and CD8 T cells and V51 γδ T cells. E) Effect of anti-V51 x PD-1 bispecific antibody and monoclonal control on downregulation of V51 TCR in V51 γδ T cells in the absence or presence of PD-1+ CD4 T cells. F) EC50 of anti-V51 x PD-1 bispecific antibody on downregulation of V51 TCR in V51 γδ T cells in the presence or absence of PD-1+ CD4 T cells. G) Effect of V51 cross-linking anti-V51 x PD-1 bispecific antibody on activation of PD-1+ T cells. [Figure 58G]V51 x PD-1 bispecific antibodies enhance activation of V51 γδ T cells and inhibit checkpoint blockade of PD-1+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-PD-1 (pembrolizumab-based), anti-RSV IgG control x anti-PD-1, and anti-V51 x anti-PD-1 (ADT1-4-2 x pembrolizumab) bispecific antibodies binding to recombinant human V51 and PD-1. B) Dual binding of anti-V51 and anti-PD-1 bispecific antibodies to recombinant human PD-1 and V51 as determined by SPR. C) PD-1 expression on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-PD-1 antibodies to PD-1+ activated CD4 and CD8 T cells and V51 γδ T cells. E) Effect of anti-V51 x PD-1 bispecific antibody and monoclonal control on downregulation of V51 TCR in V51 γδ T cells in the absence or presence of PD-1+ CD4 T cells. F) EC50 of anti-V51 x PD-1 bispecific antibody on downregulation of V51 TCR in V51 γδ T cells in the presence or absence of PD-1+ CD4 T cells. G) Effect of V51 cross-linking anti-V51 x PD-1 bispecific antibody on activation of PD-1+ T cells. [Figure 59A]V51 x 4-1BB bispecific antibodies enhance activation of V51 γδ T cells and 4-1BB+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-4-1BB (based on utomilumab), anti-RSV IgG control x anti-4-1BB (ADT1-4-2 x utomilumab), and anti-V51 x anti-4-1BB bispecific antibodies binding to recombinant human V51 and 4-1BB. B) Dual binding of anti-V51 and anti-4-1BB bispecific antibodies to recombinant human 4-1BB and V51 as determined by SPR. C) Expression of 4-1BB on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-4-1BB antibodies to 4-1BB+ activated CD8 T cells and V51 γδ T cells. E-F) Effect of anti-Vδ1 x 4-1BB bispecific antibody and monoclonal control on downregulation of Vδ1 TCR in Vδ1 γδ T cells in the absence (E) or presence (F) of 4-1BB+ CD8 T cells. G) Effect of Vδ1 cross-linking anti-Vδ1 x 4-1BB bispecific antibody on activation of 4-1BB+ T cells. [Figure 59B] V51 x 4-1BB bispecific antibodies enhance activation of V51 γδ T cells and 4-1BB+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-4-1BB (based on utomilumab), anti-RSV IgG control x anti-4-1BB (ADT1-4-2 x utomilumab), and anti-V51 x anti-4-1BB bispecific antibodies binding to recombinant human V51 and 4-1BB. B) Dual binding of anti-V51 and anti-4-1BB bispecific antibodies to recombinant human 4-1BB and V51 as determined by SPR. C) Expression of 4-1BB on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-4-1BB antibodies to 4-1BB+ activated CD8 T cells and V51 γδ T cells. E-F) Effect of anti-Vδ1 x 4-1BB bispecific antibody and monoclonal control on downregulation of Vδ1 TCR in Vδ1 γδ T cells in the absence (E) or presence (F) of 4-1BB+ CD8 T cells. G) Effect of Vδ1 cross-linking anti-Vδ1 x 4-1BB bispecific antibody on activation of 4-1BB+ T cells. [Figure 59C] V51 x 4-1BB bispecific antibodies enhance activation of V51 γδ T cells and 4-1BB+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-4-1BB (based on utomilumab), anti-RSV IgG control x anti-4-1BB (ADT1-4-2 x utomilumab), and anti-V51 x anti-4-1BB bispecific antibodies binding to recombinant human V51 and 4-1BB. B) Dual binding of anti-V51 and anti-4-1BB bispecific antibodies to recombinant human 4-1BB and V51 as determined by SPR. C) Expression of 4-1BB on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-4-1BB antibodies to 4-1BB+ activated CD8 T cells and V51 γδ T cells. E-F) Effect of anti-Vδ1 x 4-1BB bispecific antibody and monoclonal control on downregulation of Vδ1 TCR in Vδ1 γδ T cells in the absence (E) or presence (F) of 4-1BB+ CD8 T cells. G) Effect of Vδ1 cross-linking anti-Vδ1 x 4-1BB bispecific antibody on activation of 4-1BB+ T cells. [Figure 59D] V51 x 4-1BB bispecific antibodies enhance activation of V51 γδ T cells and 4-1BB+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-4-1BB (based on utomilumab), anti-RSV IgG control x anti-4-1BB (ADT1-4-2 x utomilumab), and anti-V51 x anti-4-1BB bispecific antibodies binding to recombinant human V51 and 4-1BB. B) Dual binding of anti-V51 and anti-4-1BB bispecific antibodies to recombinant human 4-1BB and V51 as determined by SPR. C) Expression of 4-1BB on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-4-1BB antibodies to 4-1BB+ activated CD8 T cells and V51 γδ T cells. E-F) Effect of anti-Vδ1 x 4-1BB bispecific antibody and monoclonal control on downregulation of Vδ1 TCR in Vδ1 γδ T cells in the absence (E) or presence (F) of 4-1BB+ CD8 T cells. G) Effect of Vδ1 cross-linking anti-Vδ1 x 4-1BB bispecific antibody on activation of 4-1BB+ T cells. [Figure 59E] V51 x 4-1BB bispecific antibodies enhance activation of V51 γδ T cells and 4-1BB+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-4-1BB (based on utomilumab), anti-RSV IgG control x anti-4-1BB (ADT1-4-2 x utomilumab), and anti-V51 x anti-4-1BB bispecific antibodies binding to recombinant human V51 and 4-1BB. B) Dual binding of anti-V51 and anti-4-1BB bispecific antibodies to recombinant human 4-1BB and V51 as determined by SPR. C) Expression of 4-1BB on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-4-1BB antibodies to 4-1BB+ activated CD8 T cells and V51 γδ T cells. E-F) Effect of anti-Vδ1 x 4-1BB bispecific antibody and monoclonal control on downregulation of Vδ1 TCR in Vδ1 γδ T cells in the absence (E) or presence (F) of 4-1BB+ CD8 T cells. G) Effect of Vδ1 cross-linking anti-Vδ1 x 4-1BB bispecific antibody on activation of 4-1BB+ T cells. [Figure 59F] V51 x 4-1BB bispecific antibodies enhance activation of V51 γδ T cells and 4-1BB+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-4-1BB (based on utomilumab), anti-RSV IgG control x anti-4-1BB (ADT1-4-2 x utomilumab), and anti-V51 x anti-4-1BB bispecific antibodies binding to recombinant human V51 and 4-1BB. B) Dual binding of anti-V51 and anti-4-1BB bispecific antibodies to recombinant human 4-1BB and V51 as determined by SPR. C) Expression of 4-1BB on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-4-1BB antibodies to 4-1BB+ activated CD8 T cells and V51 γδ T cells. E-F) Effect of anti-Vδ1 x 4-1BB bispecific antibody and monoclonal control on downregulation of Vδ1 TCR in Vδ1 γδ T cells in the absence (E) or presence (F) of 4-1BB+ CD8 T cells. G) Effect of Vδ1 cross-linking anti-Vδ1 x 4-1BB bispecific antibody on activation of 4-1BB+ T cells. [Figure 59G] V51 x 4-1BB bispecific antibodies enhance activation of V51 γδ T cells and 4-1BB+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-4-1BB (based on utomilumab), anti-RSV IgG control x anti-4-1BB (ADT1-4-2 x utomilumab), and anti-V51 x anti-4-1BB bispecific antibodies binding to recombinant human V51 and 4-1BB. B) Dual binding of anti-V51 and anti-4-1BB bispecific antibodies to recombinant human 4-1BB and V51 as determined by SPR. C) Expression of 4-1BB on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-4-1BB antibodies to 4-1BB+ activated CD8 T cells and V51 γδ T cells. E-F) Effect of anti-Vδ1 x 4-1BB bispecific antibody and monoclonal control on downregulation of Vδ1 TCR in Vδ1 γδ T cells in the absence (E) or presence (F) of 4-1BB+ CD8 T cells. G) Effect of Vδ1 cross-linking anti-Vδ1 x 4-1BB bispecific antibody on activation of 4-1BB+ T cells. [Figure 60A] V51 x OX40 bispecific antibodies enhance activation of V51 γδ T cells and OX40+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-OX40 (based on pogalizumab), anti-RSV IgG control x anti-OX40, and anti-V51 x anti-OX40 (ADT1-4-2 x pogalizumab) bispecific antibodies binding to recombinant human V51 and OX40. B) Dual binding of anti-V51 and anti-OX40 bispecific antibodies to recombinant human OX40 and V51 as determined by SPR. C) Expression of OX40 on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-OX40 antibodies to OX40+ activated CD4 T cells and V51 γδ T cells. E-F) Effect of anti-Vδ1 x OX40 bispecific antibody and monoclonal control on downregulation of Vδ1 TCR in Vδ1 γδ T cells in the absence (E) or presence (F) of OX40+ CD4 T cells. G) Effect of Vδ1 cross-linking anti-Vδ1 x OX40 bispecific antibody on activation of OX40+ T cells. [Figure 60B] V51 x OX40 bispecific antibodies enhance activation of V51 γδ T cells and OX40+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-OX40 (based on pogalizumab), anti-RSV IgG control x anti-OX40, and anti-V51 x anti-OX40 (ADT1-4-2 x pogalizumab) bispecific antibodies binding to recombinant human V51 and OX40. B) Dual binding of anti-V51 and anti-OX40 bispecific antibodies to recombinant human OX40 and V51 as determined by SPR. C) Expression of OX40 on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-OX40 antibodies to OX40+ activated CD4 T cells and V51 γδ T cells. E-F) Effect of anti-Vδ1 x OX40 bispecific antibody and monoclonal control on downregulation of Vδ1 TCR in Vδ1 γδ T cells in the absence (E) or presence (F) of OX40+ CD4 T cells. G) Effect of Vδ1 cross-linking anti-Vδ1 x OX40 bispecific antibody on activation of OX40+ T cells. [Figure 60C] V51 x OX40 bispecific antibodies enhance activation of V51 γδ T cells and OX40+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-OX40 (based on pogalizumab), anti-RSV IgG control x anti-OX40, and anti-V51 x anti-OX40 (ADT1-4-2 x pogalizumab) bispecific antibodies binding to recombinant human V51 and OX40. B) Dual binding of anti-V51 and anti-OX40 bispecific antibodies to recombinant human OX40 and V51 as determined by SPR. C) Expression of OX40 on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-OX40 antibodies to OX40+ activated CD4 T cells and V51 γδ T cells. E-F) Effect of anti-Vδ1 x OX40 bispecific antibody and monoclonal control on downregulation of Vδ1 TCR in Vδ1 γδ T cells in the absence (E) or presence (F) of OX40+ CD4 T cells. G) Effect of Vδ1 cross-linking anti-Vδ1 x OX40 bispecific antibody on activation of OX40+ T cells. [Figure 60D]V51 x OX40 bispecific antibodies enhance activation of V51 γδ T cells and OX40+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-OX40 (based on pogalizumab), anti-RSV IgG control x anti-OX40, and anti-V51 x anti-OX40 (ADT1-4-2 x pogalizumab) bispecific antibodies binding to recombinant human V51 and OX40. B) Dual binding of anti-V51 and anti-OX40 bispecific antibodies to recombinant human OX40 and V51 as determined by SPR. C) Expression of OX40 on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-OX40 antibodies to OX40+ activated CD4 T cells and V51 γδ T cells. E-F) Effect of anti-Vδ1 x OX40 bispecific antibody and monoclonal control on downregulation of Vδ1 TCR in Vδ1 γδ T cells in the absence (E) or presence (F) of OX40+ CD4 T cells. G) Effect of Vδ1 cross-linking anti-Vδ1 x OX40 bispecific antibody on activation of OX40+ T cells. [Figure 60E] V51 x OX40 bispecific antibodies enhance activation of V51 γδ T cells and OX40+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-OX40 (based on pogalizumab), anti-RSV IgG control x anti-OX40, and anti-V51 x anti-OX40 (ADT1-4-2 x pogalizumab) bispecific antibodies binding to recombinant human V51 and OX40. B) Dual binding of anti-V51 and anti-OX40 bispecific antibodies to recombinant human OX40 and V51 as determined by SPR. C) Expression of OX40 on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-OX40 antibodies to OX40+ activated CD4 T cells and V51 γδ T cells. E-F) Effect of anti-Vδ1 x OX40 bispecific antibody and monoclonal control on downregulation of Vδ1 TCR in Vδ1 γδ T cells in the absence (E) or presence (F) of OX40+ CD4 T cells. G) Effect of Vδ1 cross-linking anti-Vδ1 x OX40 bispecific antibody on activation of OX40+ T cells. [Figure 60F]V51 x OX40 bispecific antibodies enhance activation of V51 γδ T cells and OX40+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-OX40 (based on pogalizumab), anti-RSV IgG control x anti-OX40, and anti-V51 x anti-OX40 (ADT1-4-2 x pogalizumab) bispecific antibodies binding to recombinant human V51 and OX40. B) Dual binding of anti-V51 and anti-OX40 bispecific antibodies to recombinant human OX40 and V51 as determined by SPR. C) Expression of OX40 on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-OX40 antibodies to OX40+ activated CD4 T cells and V51 γδ T cells. E-F) Effect of anti-Vδ1 x OX40 bispecific antibody and monoclonal control on downregulation of Vδ1 TCR in Vδ1 γδ T cells in the absence (E) or presence (F) of OX40+ CD4 T cells. G) Effect of Vδ1 cross-linking anti-Vδ1 x OX40 bispecific antibody on activation of OX40+ T cells. [Figure 60G] V51 x OX40 bispecific antibodies enhance activation of V51 γδ T cells and OX40+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-OX40 (based on pogalizumab), anti-RSV IgG control x anti-OX40, and anti-V51 x anti-OX40 (ADT1-4-2 x pogalizumab) bispecific antibodies binding to recombinant human V51 and OX40. B) Dual binding of anti-V51 and anti-OX40 bispecific antibodies to recombinant human OX40 and V51 as determined by SPR. C) Expression of OX40 on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-OX40 antibodies to OX40+ activated CD4 T cells and V51 γδ T cells. E-F) Effect of anti-Vδ1 x OX40 bispecific antibody and monoclonal control on downregulation of Vδ1 TCR in Vδ1 γδ T cells in the absence (E) or presence (F) of OX40+ CD4 T cells. G) Effect of Vδ1 cross-linking anti-Vδ1 x OX40 bispecific antibody on activation of OX40+ T cells. [Figure 61A]V51 x TIGIT bispecific antibodies enhance activation of V51 γδ T cells and inhibit checkpoint blockade of TIGIT+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-TIGIT (based on tiragolumab), anti-RSV IgG control x anti-TIGIT, and anti-V51 x anti-TIGIT (ADT-1-4-2 x tiragolumab) bispecific antibodies binding to recombinant human V51 and TIGIT. B) Dual binding of anti-V51 and anti-TIGIT bispecific antibodies to recombinant human TIGIT and V51 as determined by SPR. C) Expression of TIGIT on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-TIGIT antibodies to TIGIT+ activated CD4 and CD8 T cells and V51 γδ T cells. E) Effect of anti-V51 x TIGIT bispecific antibody and monoclonal control on downregulation of V51 TCR in V51 γδ T cells in the absence or presence of TIGIT+ CD8 T cells. F) EC50 of anti-V51 x TIGIT bispecific antibody on downregulation of V51 TCR in V51 γδ T cells in the presence or absence of TIGIT+ CD8 T cells. G) Effect of V51 cross-linking anti-V51 x TIGIT bispecific antibody on activation of TIGIT+ T cells. [Figure 61B]V51 x TIGIT bispecific antibodies enhance activation of V51 γδ T cells and inhibit checkpoint blockade of TIGIT+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-TIGIT (based on tiragolumab), anti-RSV IgG control x anti-TIGIT, and anti-V51 x anti-TIGIT (ADT-1-4-2 x tiragolumab) bispecific antibodies binding to recombinant human V51 and TIGIT. B) Dual binding of anti-V51 and anti-TIGIT bispecific antibodies to recombinant human TIGIT and V51 as determined by SPR. C) Expression of TIGIT on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-TIGIT antibodies to TIGIT+ activated CD4 and CD8 T cells and V51 γδ T cells. E) Effect of anti-V51 x TIGIT bispecific antibody and monoclonal control on downregulation of V51 TCR in V51 γδ T cells in the absence or presence of TIGIT+ CD8 T cells. F) EC50 of anti-V51 x TIGIT bispecific antibody on downregulation of V51 TCR in V51 γδ T cells in the presence or absence of TIGIT+ CD8 T cells. G) Effect of V51 cross-linking anti-V51 x TIGIT bispecific antibody on activation of TIGIT+ T cells. [Figure 61C]V51 x TIGIT bispecific antibodies enhance activation of V51 γδ T cells and inhibit checkpoint blockade of TIGIT+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-TIGIT (based on tiragolumab), anti-RSV IgG control x anti-TIGIT, and anti-V51 x anti-TIGIT (ADT-1-4-2 x tiragolumab) bispecific antibodies binding to recombinant human V51 and TIGIT. B) Dual binding of anti-V51 and anti-TIGIT bispecific antibodies to recombinant human TIGIT and V51 as determined by SPR. C) Expression of TIGIT on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-TIGIT antibodies to TIGIT+ activated CD4 and CD8 T cells and V51 γδ T cells. E) Effect of anti-V51 x TIGIT bispecific antibody and monoclonal control on downregulation of V51 TCR in V51 γδ T cells in the absence or presence of TIGIT+ CD8 T cells. F) EC50 of anti-V51 x TIGIT bispecific antibody on downregulation of V51 TCR in V51 γδ T cells in the presence or absence of TIGIT+ CD8 T cells. G) Effect of V51 cross-linking anti-V51 x TIGIT bispecific antibody on activation of TIGIT+ T cells. [Figure 61D]V51 x TIGIT bispecific antibodies enhance activation of V51 γδ T cells and inhibit checkpoint blockade of TIGIT+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-TIGIT (based on tiragolumab), anti-RSV IgG control x anti-TIGIT, and anti-V51 x anti-TIGIT (ADT-1-4-2 x tiragolumab) bispecific antibodies binding to recombinant human V51 and TIGIT. B) Dual binding of anti-V51 and anti-TIGIT bispecific antibodies to recombinant human TIGIT and V51 as determined by SPR. C) Expression of TIGIT on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-TIGIT antibodies to TIGIT+ activated CD4 and CD8 T cells and V51 γδ T cells. E) Effect of anti-V51 x TIGIT bispecific antibody and monoclonal control on downregulation of V51 TCR in V51 γδ T cells in the absence or presence of TIGIT+ CD8 T cells. F) EC50 of anti-V51 x TIGIT bispecific antibody on downregulation of V51 TCR in V51 γδ T cells in the presence or absence of TIGIT+ CD8 T cells. G) Effect of V51 cross-linking anti-V51 x TIGIT bispecific antibody on activation of TIGIT+ T cells. [Figure 61E]V51 x TIGIT bispecific antibodies enhance activation of V51 γδ T cells and inhibit checkpoint blockade of TIGIT+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-TIGIT (based on tiragolumab), anti-RSV IgG control x anti-TIGIT, and anti-V51 x anti-TIGIT (ADT-1-4-2 x tiragolumab) bispecific antibodies binding to recombinant human V51 and TIGIT. B) Dual binding of anti-V51 and anti-TIGIT bispecific antibodies to recombinant human TIGIT and V51 as determined by SPR. C) Expression of TIGIT on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-TIGIT antibodies to TIGIT+ activated CD4 and CD8 T cells and V51 γδ T cells. E) Effect of anti-V51 x TIGIT bispecific antibody and monoclonal control on downregulation of V51 TCR in V51 γδ T cells in the absence or presence of TIGIT+ CD8 T cells. F) EC50 of anti-V51 x TIGIT bispecific antibody on downregulation of V51 TCR in V51 γδ T cells in the presence or absence of TIGIT+ CD8 T cells. G) Effect of V51 cross-linking anti-V51 x TIGIT bispecific antibody on activation of TIGIT+ T cells. [Figure 61F]V51 x TIGIT bispecific antibodies enhance activation of V51 γδ T cells and inhibit checkpoint blockade of TIGIT+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-TIGIT (based on tiragolumab), anti-RSV IgG control x anti-TIGIT, and anti-V51 x anti-TIGIT (ADT-1-4-2 x tiragolumab) bispecific antibodies binding to recombinant human V51 and TIGIT. B) Dual binding of anti-V51 and anti-TIGIT bispecific antibodies to recombinant human TIGIT and V51 as determined by SPR. C) Expression of TIGIT on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-TIGIT antibodies to TIGIT+ activated CD4 and CD8 T cells and V51 γδ T cells. E) Effect of anti-V51 x TIGIT bispecific antibody and monoclonal control on downregulation of V51 TCR in V51 γδ T cells in the absence or presence of TIGIT+ CD8 T cells. F) EC50 of anti-V51 x TIGIT bispecific antibody on downregulation of V51 TCR in V51 γδ T cells in the presence or absence of TIGIT+ CD8 T cells. G) Effect of V51 cross-linking anti-V51 x TIGIT bispecific antibody on activation of TIGIT+ T cells. [Figure 61G]V51 x TIGIT bispecific antibodies enhance activation of V51 γδ T cells and inhibit checkpoint blockade of TIGIT+ T cells. A) SPR analysis of anti-V51 (ADT1-4-2), anti-TIGIT (based on tiragolumab), anti-RSV IgG control x anti-TIGIT, and anti-V51 x anti-TIGIT (ADT-1-4-2 x tiragolumab) bispecific antibodies binding to recombinant human V51 and TIGIT. B) Dual binding of anti-V51 and anti-TIGIT bispecific antibodies to recombinant human TIGIT and V51 as determined by SPR. C) Expression of TIGIT on CD4 and CD8 T cells activated with anti-CD3 / anti-CD28 Dynabeads. D) Binding of anti-V51 and anti-TIGIT antibodies to TIGIT+ activated CD4 and CD8 T cells and V51 γδ T cells. E) Effect of anti-V51 x TIGIT bispecific antibody and monoclonal control on downregulation of V51 TCR in V51 γδ T cells in the absence or presence of TIGIT+ CD8 T cells. F) EC50 of anti-V51 x TIGIT bispecific antibody on downregulation of V51 TCR in V51 γδ T cells in the presence or absence of TIGIT+ CD8 T cells. G) Effect of V51 cross-linking anti-V51 x TIGIT bispecific antibody on activation of TIGIT+ T cells. [Figure 62] The ADCC reporter bioassay does not demonstrate ADCC as a result of anti-vδ1 antibodies. Target cells, i.e., γδ cells, were incubated with ADCC bioassay effector cells in the presence of anti-vδ1 antibodies, anti-vδ1 LAGA antibodies (Fc-disabled), and RSV isotype control. Luminescence signals were recorded as relative light units (RLU), and fold induction was calculated as described in the methods. N = 2 γδ donors (performed in technical duplicates) for "anti-vδ1 antibodies," "anti-vδ1 LAGA antibodies," "RSV," and "OKT3." N = 1 Raji cell line for the "rituximab + Raji" condition (technical duplicate). N = 1 γδ donor for the "anti-vδ1 antibodies + effector" and "anti-vδ1 LAGA antibodies + effector" conditions (performed in technical duplicate and singlet, respectively). The effector:target ratio was 3:1. [Figure 63A] Vδ1-CD19 bispecific T cell engagers enhance CD19+ target cytotoxicity and γδ T cell activation while sparing healthy CD19+ B cells. A-F) Effect of anti-Vδ1×CD19 and CD3×CD19 bispecific antibodies on γδ T cell- or αβ T cell-mediated lysis of Raji cells or healthy primary B cells. The positivity of Raji cells or healthy primary B cells was determined by confocal microscopy at 24 h in triplicate cultures of Vδ1γδ T cells with Raji cells (A) and healthy primary B cells (B); triplicate cultures of αβ T cells with Raji cells (C) and healthy primary B cells (D); or quadruplicate cultures of Vδ1γδ T cells and αβ T cells with Raji cells (E) and healthy primary B cells (F). G-I) Quantification of IL-17A secretion from γδ T cells or αβ T cells 24 hours after stimulation with anti-Vδ1×CD19 and CD3×CD19 bispecific antibodies. Cell culture supernatants from cocultures of Raji cells, primary B cells, and γδ T cells (G); or αβ T cells (H); or γδ T cells and αβ T cells (I) were collected, and IL-17A secretion was determined by MSD. The dotted line represents the minimum level of quantification. [Figure 63B]Vδ1-CD19 bispecific T cell engagers enhance CD19+ target cytotoxicity and γδ T cell activation while sparing healthy CD19+ B cells. A-F) Effect of anti-Vδ1×CD19 and CD3×CD19 bispecific antibodies on γδ T cell- or αβ T cell-mediated lysis of Raji cells or healthy primary B cells. The positivity of Raji cells or healthy primary B cells was determined by confocal microscopy at 24 h in triplicate cultures of Vδ1γδ T cells with Raji cells (A) and healthy primary B cells (B); triplicate cultures of αβ T cells with Raji cells (C) and healthy primary B cells (D); or quadruplicate cultures of Vδ1γδ T cells and αβ T cells with Raji cells (E) and healthy primary B cells (F). G-I) Quantification of IL-17A secretion from γδ T cells or αβ T cells 24 hours after stimulation with anti-Vδ1×CD19 and CD3×CD19 bispecific antibodies. Cell culture supernatants from cocultures of Raji cells, primary B cells, and γδ T cells (G); or αβ T cells (H); or γδ T cells and αβ T cells (I) were collected, and IL-17A secretion was determined by MSD. The dotted line represents the minimum level of quantification. [Figure 63C]Vδ1-CD19 bispecific T cell engagers enhance CD19+ target cytotoxicity and γδ T cell activation while sparing healthy CD19+ B cells. A-F) Effect of anti-Vδ1×CD19 and CD3×CD19 bispecific antibodies on γδ T cell- or αβ T cell-mediated lysis of Raji cells or healthy primary B cells. The positivity of Raji cells or healthy primary B cells was determined by confocal microscopy at 24 h in triplicate cultures of Vδ1γδ T cells with Raji cells (A) and healthy primary B cells (B); triplicate cultures of αβ T cells with Raji cells (C) and healthy primary B cells (D); or quadruplicate cultures of Vδ1γδ T cells and αβ T cells with Raji cells (E) and healthy primary B cells (F). G-I) Quantification of IL-17A secretion from γδ T cells or αβ T cells 24 hours after stimulation with anti-Vδ1×CD19 and CD3×CD19 bispecific antibodies. Cell culture supernatants from cocultures of Raji cells, primary B cells, and γδ T cells (G); or αβ T cells (H); or γδ T cells and αβ T cells (I) were collected, and IL-17A secretion was determined by MSD. The dotted line represents the minimum level of quantification. [Figure 63D]Vδ1-CD19 bispecific T cell engagers enhance CD19+ target cytotoxicity and γδ T cell activation while sparing healthy CD19+ B cells. A-F) Effect of anti-Vδ1×CD19 and CD3×CD19 bispecific antibodies on γδ T cell- or αβ T cell-mediated lysis of Raji cells or healthy primary B cells. The positivity of Raji cells or healthy primary B cells was determined by confocal microscopy at 24 h in triplicate cultures of Vδ1γδ T cells with Raji cells (A) and healthy primary B cells (B); triplicate cultures of αβ T cells with Raji cells (C) and healthy primary B cells (D); or quadruplicate cultures of Vδ1γδ T cells and αβ T cells with Raji cells (E) and healthy primary B cells (F). G-I) Quantification of IL-17A secretion from γδ T cells or αβ T cells 24 hours after stimulation with anti-Vδ1×CD19 and CD3×CD19 bispecific antibodies. Cell culture supernatants from cocultures of Raji cells, primary B cells, and γδ T cells (G); or αβ T cells (H); or γδ T cells and αβ T cells (I) were collected, and IL-17A secretion was determined by MSD. The dotted line represents the minimum level of quantification. [Figure 63E]Vδ1-CD19 bispecific T cell engagers enhance CD19+ target cytotoxicity and γδ T cell activation while sparing healthy CD19+ B cells. A-F) Effect of anti-Vδ1×CD19 and CD3×CD19 bispecific antibodies on γδ T cell- or αβ T cell-mediated lysis of Raji cells or healthy primary B cells. The positivity of Raji cells or healthy primary B cells was determined by confocal microscopy at 24 h in triplicate cultures of Vδ1γδ T cells with Raji cells (A) and healthy primary B cells (B); triplicate cultures of αβ T cells with Raji cells (C) and healthy primary B cells (D); or quadruplicate cultures of Vδ1γδ T cells and αβ T cells with Raji cells (E) and healthy primary B cells (F). G-I) Quantification of IL-17A secretion from γδ T cells or αβ T cells 24 hours after stimulation with anti-Vδ1×CD19 and CD3×CD19 bispecific antibodies. Cell culture supernatants from cocultures of Raji cells, primary B cells, and γδ T cells (G); or αβ T cells (H); or γδ T cells and αβ T cells (I) were collected, and IL-17A secretion was determined by MSD. The dotted line represents the minimum level of quantification. [Figure 63F]Vδ1-CD19 bispecific T cell engagers enhance CD19+ target cytotoxicity and γδ T cell activation while sparing healthy CD19+ B cells. A-F) Effect of anti-Vδ1×CD19 and CD3×CD19 bispecific antibodies on γδ T cell- or αβ T cell-mediated lysis of Raji cells or healthy primary B cells. The positivity of Raji cells or healthy primary B cells was determined by confocal microscopy at 24 h in triplicate cultures of Vδ1γδ T cells with Raji cells (A) and healthy primary B cells (B); triplicate cultures of αβ T cells with Raji cells (C) and healthy primary B cells (D); or quadruplicate cultures of Vδ1γδ T cells and αβ T cells with Raji cells (E) and healthy primary B cells (F). G-I) Quantification of IL-17A secretion from γδ T cells or αβ T cells 24 hours after stimulation with anti-Vδ1×CD19 and CD3×CD19 bispecific antibodies. Cell culture supernatants from cocultures of Raji cells, primary B cells, and γδ T cells (G); or αβ T cells (H); or γδ T cells and αβ T cells (I) were collected, and IL-17A secretion was determined by MSD. The dotted line represents the minimum level of quantification. [Figure 63G]Vδ1-CD19 bispecific T cell engagers enhance CD19+ target cytotoxicity and γδ T cell activation while sparing healthy CD19+ B cells. A-F) Effect of anti-Vδ1×CD19 and CD3×CD19 bispecific antibodies on γδ T cell- or αβ T cell-mediated lysis of Raji cells or healthy primary B cells. The positivity of Raji cells or healthy primary B cells was determined by confocal microscopy at 24 h in triplicate cultures of Vδ1γδ T cells with Raji cells (A) and healthy primary B cells (B); triplicate cultures of αβ T cells with Raji cells (C) and healthy primary B cells (D); or quadruplicate cultures of Vδ1γδ T cells and αβ T cells with Raji cells (E) and healthy primary B cells (F). G-I) Quantification of IL-17A secretion from γδ T cells or αβ T cells 24 hours after stimulation with anti-Vδ1×CD19 and CD3×CD19 bispecific antibodies. Cell culture supernatants from cocultures of Raji cells, primary B cells, and γδ T cells (G); or αβ T cells (H); or γδ T cells and αβ T cells (I) were collected, and IL-17A secretion was determined by MSD. The dotted line represents the minimum level of quantification. [Figure 63H]Vδ1-CD19 bispecific T cell engagers enhance CD19+ target cytotoxicity and γδ T cell activation while sparing healthy CD19+ B cells. A-F) Effect of anti-Vδ1×CD19 and CD3×CD19 bispecific antibodies on γδ T cell- or αβ T cell-mediated lysis of Raji cells or healthy primary B cells. The positivity of Raji cells or healthy primary B cells was determined by confocal microscopy at 24 h in triplicate cultures of Vδ1γδ T cells with Raji cells (A) and healthy primary B cells (B); triplicate cultures of αβ T cells with Raji cells (C) and healthy primary B cells (D); or quadruplicate cultures of Vδ1γδ T cells and αβ T cells with Raji cells (E) and healthy primary B cells (F). G-I) Quantification of IL-17A secretion from γδ T cells or αβ T cells 24 hours after stimulation with anti-Vδ1×CD19 and CD3×CD19 bispecific antibodies. Cell culture supernatants from cocultures of Raji cells, primary B cells, and γδ T cells (G); or αβ T cells (H); or γδ T cells and αβ T cells (I) were collected, and IL-17A secretion was determined by MSD. The dotted line represents the minimum level of quantification. [Figure 63I]Vδ1-CD19 bispecific T cell engagers enhance CD19+ target cytotoxicity and γδ T cell activation while sparing healthy CD19+ B cells. A-F) Effect of anti-Vδ1×CD19 and CD3×CD19 bispecific antibodies on γδ T cell- or αβ T cell-mediated lysis of Raji cells or healthy primary B cells. The positivity of Raji cells or healthy primary B cells was determined by confocal microscopy at 24 h in triplicate cultures of Vδ1γδ T cells with Raji cells (A) and healthy primary B cells (B); triplicate cultures of αβ T cells with Raji cells (C) and healthy primary B cells (D); or quadruplicate cultures of Vδ1γδ T cells and αβ T cells with Raji cells (E) and healthy primary B cells (F). G-I) Quantification of IL-17A secretion from γδ T cells or αβ T cells 24 hours after stimulation with anti-Vδ1×CD19 and CD3×CD19 bispecific antibodies. Cell culture supernatants from cocultures of Raji cells, primary B cells, and γδ T cells (G); or αβ T cells (H); or γδ T cells and αβ T cells (I) were collected, and IL-17A secretion was determined by MSD. The dotted line represents the minimum level of quantification. [Figure 64]Stimulation with high-affinity anti-V51 antibodies enhances 4-1BB expression on V51γδ T cells. (A) Enhanced 4-1BB expression by addition of exemplary high-affinity anti-V51 antibodies: Tissue-derived V51 T cells from four different human donors were incubated with the indicated antibodies (1 μg / ml) in the presence of THP-1 cells (2:1 E:T). After 4 h, 4-1BB expression on the surface of V51 T cells was analyzed by flow cytometry. Cells stimulated with ADT1-4-2 showed significantly increased 4-1BB expression at this time point, comparable to stimulation with OKT3 (*p<0.05, **p<0.01 by ordinary one-way ANOVA with Sidak's post-hoc test). (B, C) Enhanced expression of 4-1BB; further testing: Tissue-derived V51+ T cells were incubated with increasing amounts of ADT1-4-2 or anti-IgG1 isotype control at a 1:1 ratio in the presence of either (B) THP-1 cancer cells or (C) healthy blood-derived monocytes. After 4 hours, 4-1BB expression on the surface of V51+ T cells was analyzed by flow cytometry. Stimulation with ADT1-4-2 increased 4-1BB expression on the surface of V51 T cells. Furthermore, even though activated V51+ cells spared healthy cells (see elsewhere herein for further discussion), similar antibody-induced activation was observed when crosslinking was provided by tumor or healthy FcγR+ cells. [Figure 65]Upregulation of natural cytotoxicity receptors (NCRs) on V51 T cells in primary PBMCs. (A) Experimental culture setup including confirmatory TCR downregulation analysis: Human PBMC cultures from three different donors were incubated for 10 days with 3.33 nM of exemplary affinity-matured ADT1-4 and ADT1-7 anti-V51 antibody clones as indicated (see also B, C, and D) or an anti-RSV control. Cultures were also supplemented with 4 ng / ml IL-2 and 10 ng / ml IL-15 (Miltenyi, 130-097-746 and Peprotech, 200–15–500 ug, respectively). After 10 days of culture, % V51+ T cells were analyzed by flow cytometry. All cultures incubated with anti-V51 antibodies showed a significant reduction in detectable V51+ cells (as % pan-γ) compared to anti-RSV control cultures. Representative and typical results for one such antibody are shown here. Such analysis allows us to confirm that all affinity-matured anti-V51 antibodies included in this study showed significant target engagement and resulted in TCR downregulation. (B-D) Anti-V51 antibodies resulted in enhanced expression of NCRs (NKp30, NKp44, NKp46) on detectable V51+ cells: in addition to confirming target engagement for all anti-V51 antibodies used in this study, the expression of NCRs (NKp30, NKp44, NKp46) on gated V51+ cells was significantly reduced. The fold change in NCR was also examined. Specifically, (B) shows the fold change in the double-positive V51+, NKp30+% relative to the RSV control (RSV control normalized to the far right and expressed as 1x). (C) shows the fold change in the double-positive V51+, NKp44+% relative to the RSV control (RSV control normalized to the far right and expressed as 1x). (D) shows the fold change in the double-positive V51+, NKp46+% relative to the RSV control (RSV control normalized to the far right and expressed as 1x). These combined results highlight the consistent (donor-dependent) upregulation of NCR in detectable V51+ cells conferred by all affinity-matured anti-V51+ antibodies used in this extended 10-day primary PBMC culture system. DETAILED DESCRIPTION OF THE INVENTION

[0043] The present invention provides high affinity anti-TCR delta variable region 1 (anti-V51) antibodies, multispecific antibodies, and antibody fragments thereof. More specifically, the present invention relates to the provision and characterization of optimized antibodies, for example antibodies prepared by an optimized selection procedure starting from parent anti-V51 antibodies, such as the parent antibodies referred to herein as G04, E07, C08, B07, C05, E04, F07, G06, G09, B09, G10, and E01. In particular, the present invention relates to optimized antibodies derived from G04 and E07.

[0044] definition Unless otherwise defined, all technical and scientific terms used herein have the meaning commonly understood by one of ordinary skill in the art to which this invention belongs. As used herein, the following terms have the meanings given them below.

[0045] Gamma delta (γδ) T cells represent a small subset of T cells that express a distinct, characteristic T cell receptor (TCR) on their surface. This TCR is composed of one gamma (γ) chain and one delta (δ) chain. Each chain contains a variable (V) region, a constant (C) region, a transmembrane region, and a cytoplasmic tail. The V region contains the antigen-binding site. Two major subtypes of human γδ T cells exist: those that predominate in peripheral blood and those that predominate in nonhematopoietic tissues. The two subtypes can be defined by the type of δ and / or γ present in the cell. For example, γδ T cells that predominate in peripheral blood predominantly express the δ variable 2 chain (Vδ2). γδ T cells that predominate in nonhematopoietic tissues (i.e., are tissue-resident) predominantly express the δ variable 1 chain. Reference to "Vδ1 T cells" or "Vδ1+ T cells" refers to γδ T cells that have a Vδ1 chain, i.e., Vδ1+ cells.

[0046] Reference to "delta variable region 1" may also be referred to as V51 or Vd1, while the nucleotides encoding the TCR chain comprising this region, or the TCR protein complex comprising this region, may be referred to as "TRDV1". Any antibody or antigen-binding fragment thereof that interacts with the V51 chain of a γδ TCR is effectively an antibody or antigen-binding fragment thereof that binds to V51 and may be referred to as an "anti-TCR delta variable region 1 antibody or antigen-binding fragment thereof" or "anti-V51 antibody or antigen-binding fragment thereof" or "anti-TRDV1 antibody or antigen-binding fragment thereof".

[0047] Reference is further made herein to other δ chains, such as the "δ variable 2" chain. These may be referred to in a similar manner. For example, the δ variable 2 chain may be referred to as V52, while the nucleotides encoding the TCR chain comprising this region, or the TCR protein complex comprising this region, may be referred to as "TRDV2." In a preferred embodiment, an antibody or antigen-binding fragment thereof that interacts with the V51 chain of a γδ TCR does not interact with other δ chains, such as V52. In the present invention, the antibody is specific for TRDV1 and does not bind to TRDV2 (SEQ ID NO: 310) or other antigens present on the γδ T-cell receptor, such as TRDV3 (SEQ ID NO: 311).

[0048] Also referred to herein is a "gamma variable chain." While these may be referred to as gamma chains or Vγ, the nucleotides encoding the TCR chain comprising this region, or the TCR protein complex comprising this region, may be referred to as TRGV. For example, TRGV4 refers to the Vγ4 chain. In preferred embodiments, an antibody or antigen-binding fragment thereof that interacts with the Vδ1 chain of a γδ TCR does not interact with a gamma chain such as Vγ4 (e.g., SEQ ID NO: 309). In preferred embodiments, the antibody also does not bind to or interact with other domains found within the γδ TCR, such as TRDJ, TRDC, TRGJ, or TRGC.

[0049] The term "T cell receptor complex" refers to the complex of proteins comprising the "T cell receptor" (or "TCR") found on the surface of T cells that is responsible for the recognition of various antigens. The T cell receptor complex either comprises the α and β chains of the T cell receptor, or in the case of γδ T cells, the γ and δ chains of the T cell receptor, as well as up to six or more additional chains, e.g., CD3δ, CD3γ, CD3ε, and CD3ζ, although the exact composition of the T cell receptor complex can vary. The T cell receptor complex mediates intracellular signaling in T cells that can lead to T cell activation.

[0050] The term "antibody" encompasses any antibody protein construct comprising at least one antibody variable domain containing at least one antigen-binding site (ABS). Antibodies include, but are not limited to, immunoglobulins of the IgA, IgG, IgE, IgD, and IgM types (and their subtypes). The overall structure of immunoglobulin G (IgG) antibodies, assembled from two identical heavy (H) chains and two identical light (L) chain polypeptides, is well established and highly conserved among mammals (Padlan (1994) Mol. Immunol. 31:169-217).

[0051] A typical antibody or immunoglobulin (Ig) is a protein comprising four polypeptide chains: two heavy (H) chains and two light (L) chains. Each chain is divided into a constant region and a variable domain. The heavy (H) chain variable domain is abbreviated herein as VH, and the light (L) chain variable domain is abbreviated herein as VL. These domains, their related domains, and domains derived from them may be referred to herein as immunoglobulin chain variable domains. The VH and VL domains (also referred to as VH and VL regions) may be further divided into regions termed "complementarity-determining regions" ("CDRs"), interspersed with more conserved regions termed "framework regions" ("FRs"). Framework regions and complementarity-determining regions have been precisely defined (Kabat et al., Sequences of Proteins of Immunological Interest, Fifth Edition, USDapartment of Health and Human Services, (1991) NIH Publication Number 91-3242). Other numbering conventions for CDR sequences exist, such as those described in Chothia et al. (1989) Nature 342:877-883 or compiled by IMGT.org. In a conventional antibody, each VH and VL is composed of three CDRs and four FRs, arranged from the amino terminus to the carboxy terminus in the following order: FR1, CDR1, FR2, CDR2, FR3, CDR3, FR4. A conventional antibody tetramer, consisting of two immunoglobulin heavy chains and two immunoglobulin light chains, is formed by the immunoglobulin heavy and light chains interconnected by disulfide bonds, and the heavy chains similarly interconnected. The heavy chain constant region contains three domains, CH1, CH2, and CH3. The light chain constant region is composed of one domain, CL. The heavy chain variable domain and the light chain variable domain are binding domains that interact with antigens. The constant regions of the antibodies typically mediate the binding of the antibody to host tissues or factors, including various cells of the immune system (e.g., effector cells) and the first component (C1q) of the classical complement system.

[0052] As used herein, a "fragment" of an antibody (which may also be referred to as an "antibody fragment," "immunoglobulin fragment," "antigen-binding fragment," or "antigen-binding polypeptide") refers to a portion of an antibody (or construct comprising such a portion) that specifically binds to the target, the delta variable region 1 (Vδ1) chain of the gamma delta T cell receptor (e.g., a molecule in which one or more immunoglobulin chains are not full length but which specifically binds to the target). Examples of binding fragments encompassed by the term antibody fragment include: (i) Fab fragment (a monovalent fragment consisting of the VL, VH, CL, and CH1 domains); (ii) F(ab′)2 fragment (a bivalent fragment consisting of two Fab fragments linked by a disulfide bridge at the hinge region); (iii) Fd fragment (consisting of the VH and CH1 domains); (iv) Fv fragment (consisting of the VL and VH domains of a single arm of an antibody); (v) single-chain variable fragments (scFv) (consisting of VL and VH domains linked by a synthetic linker that allows the VL and VH regions to be produced using recombinant methods as a single protein chain to form a monovalent molecule); (vi) VH (immunoglobulin chain variable domain consisting of a VH domain); (vii) VL (immunoglobulin chain variable domain consisting of a VL domain); (viii) domain antibodies (dAbs) (consisting of either a VH or VL domain); (ix) a minibody (consisting of a pair of scFv fragments linked by a CH3 domain); and (x) Diabodies, which consist of a non-covalent dimer of scFv fragments consisting of the VH domain from one antibody linked to the VL domain from another antibody by a small peptide linker.

[0053] A "human antibody" refers to an antibody having variable and constant regions derived from human germline immunoglobulin sequences. A human subject administered such a human antibody does not mount a cross-species antibody response (e.g., referred to as a HAMA (human anti-mouse antibody) response) to primary amino acids contained within the antibody. Such human antibodies may contain amino acid residues (e.g., mutations introduced by random or site-specific mutagenesis or somatic mutation) not encoded by human germline immunoglobulin sequences, for example, in the CDRs, particularly CDR3. However, this term is not intended to encompass antibodies in which CDR sequences derived from the germline of another mammalian species, such as a mouse, have been grafted onto human framework sequences. Human antibodies that are prepared, expressed, produced, or isolated by recombinant means, e.g., antibodies expressed using a recombinant expression vector transfected into a host cell, antibodies isolated from the combination of a recombinant human antibody library, antibodies isolated from an animal (e.g., a mouse) transgenic for human immunoglobulin genes, or antibodies prepared, expressed, produced, or isolated by any other means, including splicing human immunoglobulin gene sequences into other DNA sequences, may also be referred to as "recombinant human antibodies."

[0054] The replacement of at least one amino acid residue in a framework region of a non-human immunoglobulin variable domain with the corresponding residue from a human variable domain is called "humanization." Humanization of variable domains can reduce immunogenicity in humans.

[0055] "Specificity" refers to the number of different antigens or antigenic determinants to which a particular antibody or antigen-binding fragment thereof can bind. Antibody specificity is the antibody's ability to recognize a particular antigen as a unique molecular entity and distinguish it from other antigens. An antibody that "specifically binds" to an antigen or epitope is a term well understood in the art. A molecule is said to exhibit "specific binding" if it reacts with a particular target antigen or epitope more frequently, more rapidly, with a longer duration, and / or with a higher affinity than it reacts with other targets. An antibody "specifically binds" to a target antigen or epitope if it binds with higher affinity, higher avidity, more readily, and / or with a longer duration than it binds to other substances.

[0056] The antibodies of the present invention include monospecific antibodies (i.e., antibodies that bind to only one antigen) and multispecific antibodies. A "multispecific antibody" is an antibody that can bind to multiple different epitopes simultaneously or sequentially. Generally, these epitopes do not exist on the same antigen. Thus, a multispecific antibody has the ability to selectively bind to epitopes present on different antigens via multiple different binding domains. This contrasts with conventional monospecific antibodies, which do not have this ability. To be precise, a "monospecific antibody" specifically binds to only one antigen, but may have multiple binding sites for this antigen (e.g., a fully human IgG antibody has a valency of 2, while other antibodies may have a higher valency, but if the antibody recognizes only one antigen, it is still classified as a monospecific antibody). Thus, the multispecific antibody of the present invention binds to multiple different antigens simultaneously and / or sequentially.

[0057] In some embodiments of the present invention, the antibody is a bispecific antibody. A "bispecific antibody" is an antibody that can bind to two different epitopes simultaneously and / or sequentially. Generally, these epitopes do not occur on the same antigen. Thus, a bispecific antibody has the ability to selectively bind to two different epitopes present on two different antigens via two different binding domains. This is in contrast to conventional monospecific antibodies, which do not have this ability. Thus, the bispecific antibodies of the present invention bind to two different antigens simultaneously and / or sequentially.

[0058] "Affinity," expressed by the equilibrium constant (KD) for the dissociation of an antigen with an antigen-binding polypeptide, is a measure of the binding strength between an antigenic determinant and an antigen-binding site on an antibody (or its antigen-binding fragment). The smaller the KD value, the stronger the binding strength between an antigenic determinant and an antigen-binding polypeptide. Alternatively, affinity can be expressed as an affinity constant (KA), which is 1 / KD. Affinity can be determined by known methods depending on the specific antigen of interest. For example, KD can be determined by surface plasmon resonance.

[0059] 10 -6 Any KD value less than 0.05 is considered to indicate binding. Specific binding of an antibody or antigen-binding fragment thereof to an antigen or antigenic determinant can be measured by any suitable known method, including, for example, Scatchard analysis and / or competitive binding assays, such as radioimmunoassays (RIAs), enzyme immunoassays (EIAs), and sandwich competition assays, equilibrium dialysis, equilibrium binding, gel filtration, ELISA, surface plasmon resonance, or spectroscopy (e.g., using fluorescence assays), and various modifications thereof known in the art.

[0060] "Avidity" is a measure of the strength of binding between an antibody or antigen-binding fragment thereof and an antigen of interest. Avidity is related to both the affinity between an antigenic determinant and its antigen-binding site on the antibody and the number of pertinent binding sites present on the antibody.

[0061] "In situ" means in its native or original location, rather than transferred to another location. For example, V51 cells in situ in a patient refer to in vivo v51 cells, as opposed to cells in vitro or ex vivo.

[0062] "Human tissue V51+ cells," as well as "hematopoietic and blood V51+ cells" and "tumor-infiltrating lymphocyte (TIL) V51+ cells" are defined as V51+ cells contained in or derived from either human tissues or the hematopoietic blood system or human tumors, respectively. All of the above cell types can be identified by their (i) location or where they originate, and (ii) their V51+ TCR expression.

[0063] A "modulatory antibody" is an antibody that, upon contact with or binding to a cell expressing a target to which the antibody binds, produces a measurable change, including but not limited to, a measurable change in cell cycle, and / or cell number, and / or cell viability, and / or one or more cell surface markers, and / or secretion of one or more secreted molecules (e.g., cytokines, chemokines, leukotrienes, etc.), and / or function (e.g., cytotoxicity towards target or diseased cells). A method of "modulating" a cell or population thereof refers to a method in which at least one measurable change in the cell or cells or secretions therefrom is induced to produce one or more "modulated cells."

[0064] An "immune response" is a measurable change in at least one cell, or one cell type, or one endocrine pathway, or one exocrine pathway of the immune system (including but not limited to, a cellular response, a humoral response, a cytokine response, or a chemokine response) upon addition of a regulatory antibody.

[0065] "Immune cells" are defined as cells of the immune system, including, but not limited to, CD34+ cells, B cells, CD45+ (lymphocyte common antigen) cells, αβ T cells, cytotoxic T cells, helper T cells, plasma cells, neutrophils, monocytes, macrophages, erythrocytes, platelets, dendritic cells, phagocytes, granulocytes, innate lymphoid cells, natural killer (NK) cells, and γδ T cells. Typically, combinatorial cell surface molecule analysis (e.g., by flow cytometry) is used to classify immune cells to identify them or to group or cluster them into distinct subpopulations, which can then be further subdivided by additional analyses. For example, CD45+ lymphocytes can be further subdivided into vδ-positive and vδ-negative populations.

[0066] A "model system" is a living model or biological representation designed to aid in understanding the extent to which a pharmaceutical agent, such as an antibody or antigen-binding fragment thereof, may function as a drug in ameliorating the signs or symptoms of a disease. Such models typically involve the use of in vitro, ex vivo, and in vivo diseased, non-diseased, healthy, effector cells, and tissues in which the performance of the agent can be studied and compared.

[0067] A "pathological cell" exhibits a phenotype associated with a disease such as cancer, an infection such as a viral infection, or the progression of an inflammatory condition or disease. For example, a pathological cell can be a tumor cell, an autoimmune tissue, or a virally infected cell. Thus, the pathological cell can be defined as tumorous, virally infected, or inflammatory.

[0068] "Healthy cells" refer to normal cells that are not affected by a disease. These may also be referred to as "normal" cells or "non-diseased" cells. Non-diseased cells include non-cancerous cells, or non-infected cells, or non-inflammatory cells. Such cells are often used in conjunction with related diseased cells to measure the diseased cell specificity exerted by a drug and / or to better understand the therapeutic index of a drug.

[0069] "Disease cell specificity" is a measure of how effective an effector cell or population thereof (e.g., a V51+ cell population) is at distinguishing and killing diseased cells, such as cancer cells, while sparing non-diseased or healthy cells. This ability can be measured in a model system and can involve comparing the tendency of an effector cell or effector cell population to selectively kill or lyse diseased cells to the ability of the effector cells to kill or lyse non-diseased or healthy cells. The diseased cell specificity can provide information about the potential therapeutic index of a drug.

[0070] "Enhanced disease cell specificity" refers to the phenotype of an effector cell, e.g., V51+ cell, or population thereof, that has been modulated to further enhance its ability to specifically kill disease cells. This enhancement can be measured in various ways, including the fold change or percent increase in specificity or selectivity of disease cell killing.

[0071] "ADCC" or "antibody-dependent cellular cytotoxicity" refers to an immune response against cells coated with antibodies that bind to cell surface antigens. It is a cell-mediated process in which immune effector cells (e.g., NK cells) recognize the cell-bound antibodies and cause degranulation and lysis of the target cell. Typically, this is mediated by Fc-Fcγ interactions. The Fc region of the cell-bound antibody recruits effector cells (e.g., NK cells) that express Fcγ receptors, resulting in effector cell degranulation and target cell killing.

[0072] "Fc-enabled" refers to an antibody that contains a functional Fc region (crystallizable region), i.e., an Fc region that has not been mutated or otherwise disabled. An Fc-enabled antibody exhibits unattenuated Fc function. An Fc-enabled antibody may contain a human IGHC heavy chain sequence listed in IMGT that has not been modified, engineered, or constructed to reduce binding to one or more Fcγ receptors. For example, by mutation of the IGHC hinge or by construction of an antibody containing a heavy chain constant domain that is a chimeric or hybrid of IgG1 / IgG2A or IgG1 / IgG4 IGHC sequences.

[0073] Preferably, the antibodies or antigen-binding fragments thereof (i.e., polypeptides) of the present invention are isolated. An "isolated" polypeptide is one that has been removed from its original environment. The term "isolated" may be used to refer to an antibody that is substantially free of other antibodies with different antigenic specificities (e.g., an isolated antibody or fragment thereof that specifically binds to Vδ1 is substantially free of antibodies that specifically bind to antigens other than Vδ1). The term "isolated" may also be used to refer to a preparation in which the isolated antibody is sufficiently pure to be administered therapeutically when formulated as the active ingredient of a pharmaceutical composition, or is at least 70-80% (w / w) pure, more preferably at least 80-90% (w / w) pure, even more preferably 90-95% pure, and most preferably at least 95%, 96%, 97%, 98%, 99%, or 100% (w / w) pure.

[0074] Preferably, the polynucleotide used in the present invention is isolated.An "isolated" polynucleotide is one that is removed from its original environment.For example, a naturally occurring polynucleotide is isolated if it is separated from some or all of the materials that coexist in natural system.For example, a polynucleotide is considered to be isolated if it is cloned into a vector that is not part of its natural environment, or if it is contained in cDNA.

[0075] An antibody or antigen-binding fragment thereof may be a "functionally active variant," including naturally occurring allelic variants, mutants, or any other non-naturally occurring variants. As known in the art, allelic variants are alternative forms of (poly)peptides characterized by one or more amino acid substitutions, deletions, or additions that do not essentially alter the biological function of the polypeptide. As non-limiting examples, such functionally active variants may still function if the framework containing the CDRs is modified, the CDRs themselves are modified, the CDRs are grafted onto alternative frameworks, or N- or C-terminal extensions are incorporated. Furthermore, CDR-containing binding domains may be paired with different partner chains, such as those shared with another antibody. The binding domains may still function if shared with a so-called "common" light chain or a "common" heavy chain. Furthermore, the binding domains may function when multimerized. Furthermore, "antibody or antigen-binding fragment thereof" can also include functional variants in which the VH or VL or constant domains have been altered away from or towards different canonical sequences (e.g., those listed at IMGT.org) and still function.

[0076] For comparing two closely related polypeptide sequences, the "% sequence identity" between a first polypeptide sequence and a second polypeptide sequence can be calculated using NCBI BLAST v2.0 with standard settings for polypeptide sequences (BLASTP). For comparing two closely related polynucleotide sequences, the "% sequence identity" between a first polynucleotide sequence and a second polynucleotide sequence can be calculated using NCBI BLAST v2.0 with standard settings for nucleotide sequences (BLASTN).

[0077] A polypeptide or polynucleotide sequence is said to be the same as, or "identical to," another polypeptide or polynucleotide sequence if they share 100% sequence identity over their entire length. Residues within a sequence are numbered from left to right, i.e., from N-terminus to C-terminus for polypeptides; from 5'-terminus to 3'-terminus for polynucleotides.

[0078] In some embodiments, any particular % sequence identity of a sequence is calculated without the sequences of all six CDRs of the antibody. For example, an anti-V51 antibody or antigen-binding fragment thereof may comprise a heavy chain variable region sequence that is at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to a particular heavy chain variable region sequence, and / or a light chain variable region sequence that is at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to a particular light chain variable region sequence, wherein any amino acid diversity occurs only in the framework regions of the heavy and light chain variable region sequences. In such embodiments, an anti-V51 antibody or antigen-binding fragment thereof with a particular sequence identity retains the complete CDR1, CDR2, and CDR3 sequences of the heavy and light chains of the corresponding anti-V51 antibody or antigen-binding fragment thereof. A more specific example, which is in no way limiting and is intended solely to further illustrate these embodiments of the invention, provides an anti-V51 antibody or antigen-binding fragment thereof comprising a VH comprising, or consisting of, an amino acid sequence at least 90% identical to the amino acid sequence of SEQ ID NO: 15, and a VL comprising, or consisting of, an amino acid sequence at least 90% identical to the amino acid sequence of SEQ ID NO: 40, wherein any amino acid diversity occurs only in the framework regions of the heavy and light chain variable region sequences. Thus, the antibody of this exemplary embodiment further comprises a VHDR1 comprising the amino acid sequence of SEQ ID NO: 51, a VHDR2 comprising the amino acid sequence of SEQ ID NO: 53, a VHDR3 comprising the amino acid sequence of SEQ ID NO: 68, a VLDR1 comprising the amino acid sequence of SEQ ID NO: 79, a VLDR2 comprising the amino acid sequence of SEQ ID NO: 80, and a VLDR3 comprising the amino acid sequence of SEQ ID NO: 95.

[0079] Furthermore, the antibodies and antigen-binding fragments thereof provided herein comprise a κ light chain variable sequence and may retain an amino acid residue at position 74 according to the IMGT numbering system that is not serine, e.g., a non-polar and / or non-germlined residue, e.g., they comprise a leucine residue at this position. For example, and by no means limiting, and merely to further illustrate these embodiments of the invention, there is provided an anti-Vδ1 antibody or antigen-binding fragment thereof comprising a VH comprising, or consisting of, an amino acid sequence at least 90% identical to the amino acid sequence of SEQ ID NO: 15, and a VL comprising, or consisting of, an amino acid sequence at least 90% identical to the amino acid sequence of SEQ ID NO: 40, wherein any amino acid diversity occurs only in the framework regions of the heavy chain variable region sequence and the light chain variable region sequence, and wherein the antibody comprises a κ light chain variable sequence that comprises an amino acid residue at position 74 according to the IMGT numbering system that is non-germline and / or non-polar (e.g., a leucine residue at this position). The antibody of this specific example further comprises a VHCDR1 comprising the amino acid sequence of SEQ ID NO: 51, a VHCDR2 comprising the amino acid sequence of SEQ ID NO: 53, a VHCDR3 comprising the amino acid sequence of SEQ ID NO: 68, a VLCDR1 comprising the amino acid sequence of SEQ ID NO: 79, a VLCDR2 comprising the amino acid sequence of SEQ ID NO: 80, and a VLCDR3 comprising the amino acid sequence of SEQ ID NO: 95.

[0080] A "difference" between sequences refers to the insertion, deletion, or substitution of a single amino acid residue at a position in a second sequence compared to a first sequence. Two polypeptide sequences can contain one, two, or more such amino acid differences. An insertion, deletion, or substitution in a second sequence that is otherwise identical to a first sequence (100% sequence identity) results in a decrease in the percent sequence identity. For example, if an identical sequence is 9 amino acid residues long, a single substitution in the second sequence results in 88.9% sequence identity. If a first polypeptide sequence and a second polypeptide sequence are 9 amino acid residues long and share six identical residues, the first polypeptide sequence and the second polypeptide sequence share more than 66% identity (the first polypeptide sequence and the second polypeptide sequence share 66.7% identity).

[0081] Alternatively, to compare a first reference polypeptide sequence with a second comparison polypeptide sequence, the number of additions, substitutions, and / or deletions made to the first sequence to generate the second sequence can be determined. An "addition" is the addition of one amino acid residue to the sequence of the first polypeptide (including additions at either end of the first polypeptide). A "substitution" is the replacement of one amino acid residue in the sequence of the first polypeptide with a different amino acid residue. Such substitutions can be conservative or non-conservative. A "deletion" is the removal of one amino acid residue from the sequence of the first polypeptide (including deletions at either end of the first polypeptide).

[0082] Using the three-letter and one-letter codes, naturally occurring amino acids can be referred to as follows: glycine (G or Gly), alanine (A or Ala), valine (V or Val), leucine (L or Leu), isoleucine (I or Ile), proline (P or Pro), phenylalanine (F or Phe), tyrosine (Y or Tyr), tryptophan (W or Trp), lysine (K or Lys), arginine (R or Arg), histidine (H or His), aspartic acid (D or Asp), glutamic acid (E or Glu), asparagine (N or Asn), glutamine (Q or Gln), cysteine ​​(C or Cys), methionine (M or Met), serine (S or Ser), and threonine (T or Thr). When the residue can be aspartic acid or asparagine, the symbols Asx or B can be used. Where the residue may be any amino acid, the symbol Xaa or X may be used. Where the residue may be glutamic acid or glutamine, the symbol Glx or Z may be used. Unless the context dictates otherwise, a reference to aspartic acid includes aspartate and a reference to glutamic acid includes glutamate.

[0083] As used herein, the numbering of polypeptide sequences and the definitions of CDRs and FRs are as defined according to the EU and / or IMGT numbering system, as indicated by the context. "Corresponding" amino acid residues between a first polypeptide sequence and a second polypeptide sequence are amino acid residues in the first sequence that share the same position as the amino acid residues in the second sequence according to the EU and / or IMGT numbering system, as indicated by the context, but the amino acid residues in the second sequence may differ in identity from the first sequence. Preferably, corresponding residues share the same number (and letter) when the framework and CDRs are the same length according to the EU or IMGT definition. Alignment can be achieved manually or by using known computer algorithms for sequence alignment, such as, for example, NCBI BLAST v2.0 (BLASTP or BLASTN) using standard settings.

[0084] References to "epitope" herein refer to the portion of a target that is specifically bound by an antibody or its antigen-binding fragment. An epitope can also be referred to as an "antigenic determinant." An antibody binds to "essentially the same epitope" as another antibody when they both recognize the same or sterically overlapping epitopes. A commonly used method for determining whether two antibodies bind to the same or overlapping epitopes is a competitive assay, which can be configured in a number of different formats using either labeled antigen or labeled antibody (e.g., well plates using radioactive or enzyme labels, or flow cytometry on cells expressing the antigen). An antibody binds to the "same epitope" as another antibody when they both recognize the same epitope (i.e., all contact points between the antigen and the antibody are the same).

[0085] Epitopes found in protein targets can be defined as "linear epitopes" or "conformational epitopes." Linear epitopes are formed by contiguous sequences of amino acids in the protein antigen. Conformational epitopes are formed from amino acids that are discontinuous within the protein sequence but are brought together when the protein folds into a three-dimensional structure.

[0086] As used herein, the term "vector" is intended to refer to a nucleic acid molecule capable of transporting another nucleic acid to which it has been linked. One type of vector is a "plasmid," which refers to a circular double-stranded DNA loop into which additional DNA segments can be ligated. Another type of vector is a viral vector, into which additional DNA segments can be ligated. Certain vectors are capable of autonomous replication in a host cell into which they are introduced (e.g., bacterial vectors having a bacterial origin of replication and episomal mammalian and yeast vectors). Other vectors (e.g., non-episomal mammalian vectors) can be integrated into the genome of a host cell upon introduction into the host cell, and thereby are replicated along with the host genome. Moreover, certain vectors are capable of directing the expression of genes to which they are operably linked. Such vectors are referred to herein as "recombinant expression vectors" or simply "expression vectors." In general, expression vectors useful in recombinant DNA techniques are often in the form of plasmids. As the plasmid is the most commonly used form of vector, "plasmid" and "vector" may be used interchangeably herein. However, the invention is intended to encompass other forms of expression vectors, such as viral vectors (e.g., replication-defective retroviruses, adenoviruses, and adeno-associated viruses), and even bacteriophage and phagemid systems, which serve equivalent functions. As used herein, the term "recombinant host cell" (or simply "host cell") is intended to refer to a cell into which a recombinant expression vector has been introduced. Such terms are intended to refer not only to the particular subject cell, but also to progeny of such cells, for example, when used to create cell lines or cell banks that are then optionally stored, provided, sold, given away, or used to produce antibodies or antigen-binding fragments thereof described herein.

[0087] Reference to a "subject," "patient," or "individual" refers to a subject to be treated, particularly a mammalian subject. Mammalian subjects include humans, non-human primates, farm animals (e.g., cows), sport animals, or pets, such as dogs, cats, guinea pigs, rabbits, rats, or mice. In some embodiments, the subject is a human. In alternative embodiments, the subject is a non-human mammal, such as a mouse.

[0088] The term "sufficient amount" means an amount sufficient to cause a desired effect. The term "therapeutically effective amount" is an amount effective to ameliorate the symptoms of a disease or disorder. A therapeutically effective amount can be a "prophylactically effective amount" where prevention can be considered treatment.

[0089] A disease or disorder is "alleviated" if the severity of a sign or symptom of the disease or disorder, the frequency with which such sign or symptom is experienced by a subject, or both, are reduced (compared to an earlier time point, e.g., before administration of any antibody).

[0090] As used herein, "treating a disease or disorder" means reducing the frequency and / or severity of at least one sign or symptom of the disease or disorder experienced by a subject (compared to an earlier time point, e.g., before administration of any antibody).

[0091] As used herein, "cancer" refers to the abnormal growth or division of cells. Generally, the growth and / or lifespan of cancer cells exceeds and is uncoordinated with the growth and / or lifespan of surrounding normal cells and tissues. Cancers can be benign, pre-malignant, or malignant. Cancers arise in a variety of cells and tissues, including the oral cavity (e.g., mouth, tongue, pharynx, etc.), digestive system (e.g., esophagus, stomach, small intestine, colon, rectum, liver, bile duct, gallbladder, pancreas, etc.), respiratory system (e.g., larynx, lungs, bronchi, etc.), bones, joints, skin (e.g., basal cell, squamous cell, meningioma, etc.), breast, reproductive system (e.g., uterus, ovaries, prostate, testes, etc.), urinary system (e.g., bladder, kidneys, ureters, etc.), eyes, nervous system (e.g., brain, etc.), endocrine system (e.g., thyroid, etc.), and hematopoietic system (e.g., lymphoma, myeloma, leukemia, acute lymphocytic leukemia, chronic lymphocytic leukemia, acute myeloid leukemia, chronic myeloid leukemia, etc.).

[0092] As used herein, the term "about" as used herein includes up to 10% above and below the specified value, preferably up to 5% above and below the specified value, and particularly includes the specified value. The term "between" includes the boundary values ​​specified.

[0093] Antibodies and antigen-binding fragments thereof Provided herein is an antibody or antigen-binding fragment thereof capable of specifically binding to the delta variable 1 chain (Vδ1) of the gamma delta T cell receptor (TCR). The present invention relates to the use of said antibody as a medicament for administration to a subject to be treated.

[0094] In one embodiment, the antibody or antigen-binding fragment thereof is an scFv, Fab, Fab', F(ab'), Fv, a variable domain (e.g., VH or VL), a diabody, a minibody, or a monoclonal antibody. In a further embodiment, the antibody or antigen-binding fragment thereof is an scFv.

[0095] The antibodies of the present invention can be of any class, e.g., IgG, IgA, IgM, IgE, IgD, or their isotypes, and can contain a kappa or lambda light chain. In one embodiment, the antibody is an IgG antibody, e.g., at least one of the isotypes IgG1, IgG2, IgG3, or IgG4. In further embodiments, the antibody can be in a format, such as an IgG format, with an Fc mutated to confer desired properties, e.g., to reduce effector function, extend half-life, alter ADCC, or improve hinge stability. Such modifications are well known in the art.

[0096] In one embodiment, the antibody or antigen-binding fragment thereof is human. Thus, the antibody or antigen-binding fragment thereof may be derived from a human immunoglobulin (Ig) sequence. The CDRs, framework, and / or constant regions of the antibody (or antigen-binding fragment thereof) may be derived from a human Ig sequence, particularly a human IgG sequence. The CDRs, framework, and / or constant regions may be substantially identical to the human Ig sequence, particularly a human IgG sequence. The advantage of using human antibodies is that they are less immunogenic or non-immunogenic in humans.

[0097] The antibody or antigen-binding fragment thereof may be chimeric, for example, a mouse / human chimeric antibody.

[0098] Alternatively, the antibody or antigen-binding fragment thereof is derived from a non-human species, such as mouse. Such non-human antibodies can be modified to increase their similarity to antibody variants naturally produced in humans, thereby making the antibody or antigen-binding fragment thereof partially or fully humanized. Thus, in one embodiment, the antibody or antigen-binding fragment thereof is humanized.

[0099] Overview of the specific antibodies provided herein A summary of some of the specific antigen-binding molecules (i.e., antibodies) provided by the present invention is provided below, along with the assigned SEQ ID NOs in the accompanying sequence listing. Antigen-binding variants, derivatives, and fragments thereof are also provided as part of the present invention. The sequences are shown in the accompanying sequence listing and in the accompanying figures. In the event of discrepancies between the sequences in the sequence listing and those in Figures 45-48, the sequences in the figures shall prevail. [Table 1-1] [Table 1-2] [Table 2-1] [Table 2-2] [Table 3] [Table 4] [Table 5]

[0100] Antibodies derived from ADT1-4 and ADT1-7 The present invention provides antibodies derived from the parent antibody ADT1-4 (having a heavy chain variable region sequence set forth in SEQ ID NO: 1 and a light chain variable region sequence set forth in SEQ ID NO: 26), and antibodies derived from the parent antibody ADT1-7 (having a heavy chain variable region sequence set forth in SEQ ID NO: 106 and a light chain variable region sequence set forth in SEQ ID NO: 118). ADT1-4 is also referred to herein as G04, and ADT1-4 and G04 are used interchangeably. ADT1-7 is also referred to herein as E07, and ADT1-7 and E07 are used interchangeably.

[0101] In some embodiments, the invention provides an anti-TCR delta variable region 1 (anti-V51) antibody or antigen-binding fragment thereof comprising: a heavy chain variable region comprising, or consisting of, a VH CDR3 comprising an amino acid sequence having at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a sequence selected from the group consisting of SEQ ID NOs: 55 to 78 and 133 to 143; and / or a light chain variable region comprising, or consisting of, a VL CDR3 comprising an amino acid sequence having at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a sequence selected from the group consisting of SEQ ID NOs: 82 to 105 and 147 to 157. Certain amino acid substitutions can be made to provide one or more of the variant antibodies described herein.

[0102] In some embodiments, the invention provides an anti-TCR delta variable region 1 (anti-V51) antibody or antigen-binding fragment thereof comprising: a VHCDR1 comprising or consisting of an amino acid sequence having at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a sequence selected from the group consisting of SEQ ID NOs: 51, 52, and 130; a VHCDR2 comprising or consisting of an amino acid sequence having at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a sequence selected from the group consisting of SEQ ID NOs: 53 and 131; and A heavy chain variable region comprising a VHCDR3 comprising or consisting of an amino acid sequence having at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a sequence selected from the group consisting of SEQ ID NOs: 55-78 and 133-143; and VLCDR1 comprising or consisting of an amino acid sequence having at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a sequence selected from the group consisting of SEQ ID NOs: 79 and 144; a VLCDR2 comprising or consisting of an amino acid sequence having at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a sequence selected from the group consisting of SEQ ID NOs: 80 and 145; and A light chain variable region comprising a VLCDR3 comprising or consisting of an amino acid sequence having at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a sequence selected from the group consisting of SEQ ID NOs: 82 to 105 and 147 to 157.

[0103] Certain amino acid substitutions can be made to provide one or more of the variant antibodies described herein.

[0104] In some embodiments, the invention provides an anti-TCR delta variable region 1 (anti-V51) antibody or antigen-binding fragment thereof comprising: a heavy chain variable region comprising or consisting of a sequence having at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a sequence selected from the group consisting of SEQ ID NOs: 2-25 and 107-117; and / or A light chain variable region comprising, or consisting of, a sequence having at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a sequence selected from the group consisting of SEQ ID NOs: 27 to 50 and 119 to 129.

[0105] Antibodies derived from ADT1-4 The present invention provides antibodies derived from the parent antibody ADT1-4 (having a heavy chain variable region sequence set forth in SEQ ID NO: 1 and a light chain variable region sequence set forth in SEQ ID NO: 26), for example, as described below. ADT1-4 is also referred to herein as G04, and ADT1-4 and G04 are used interchangeably.

[0106] Antibodies containing specific CDR sequences derived from ADT1-4 The antibodies provided herein include the following antibodies having specific sequences derived from ADT1-4:

[0107] For example, some embodiments provide an anti-TCRδ variable region 1 (anti-Vδ1) antibody or antigen-binding fragment thereof, comprising a heavy chain variable region comprising a VH CDR3 comprising, or consisting of, an amino acid sequence selected from the group consisting of SEQ ID NOs: 55 to 78; and / or a light chain variable region comprising a VL CDR3 comprising, or consisting of, an amino acid sequence selected from the group consisting of SEQ ID NOs: 82 to 105. Certain amino acid substitutions can be made to provide one or more of the variant antibodies described herein.

[0108] In some embodiments, an anti-TCRδ variable region 1 (anti-Vδ1) antibody or antigen-binding fragment thereof is provided, comprising a heavy chain variable region comprising a VH CDR3 comprising, or consisting of, an amino acid sequence selected from the group consisting of SEQ ID NOs: 55 to 77; and / or a light chain variable region comprising a VL CDR3 comprising, or consisting of, an amino acid sequence selected from the group consisting of SEQ ID NOs: 82 to 104. Certain amino acid substitutions can be made to provide one or more of the variant antibodies described herein.

[0109] In some embodiments, there is provided an anti-TCR delta variable region 1 (anti-V51) antibody or antigen-binding fragment thereof comprising a heavy chain variable region comprising a VH CDR3 comprising, or consisting of, an amino acid sequence selected from the group consisting of SEQ ID NOs: 58, 60, 61, 62, 65, 66, 68, 74, 76, and 77; and / or a light chain variable region comprising a VL CDR3 comprising, or consisting of, an amino acid sequence selected from the group consisting of SEQ ID NOs: 85, 87, 88, 89, 92, 93, 95, 101, 103, and 104. Certain amino acid substitutions may be made to provide one or more of the variant antibodies described herein.

[0110] Also provided are anti-TCR delta variable region 1 (anti-V51) antibodies or antigen-binding fragments thereof, comprising: VHCDR1 comprising or consisting of an amino acid sequence selected from the group consisting of SEQ ID NOs: 51 and 52; VHCDR2 comprising or consisting of the amino acid sequence of SEQ ID NO: 53; and A heavy chain variable region comprising a VHCDR3 comprising or consisting of an amino acid sequence selected from the group consisting of SEQ ID NOs: 55 to 78, and VLCDR1 comprising or consisting of the amino acid sequence of SEQ ID NO: 79; VLCDR2 comprising or consisting of the amino acid sequence of SEQ ID NO: 80; and A light chain variable region comprising a VLCDR3 comprising or consisting of an amino acid sequence selected from the group consisting of SEQ ID NOs: 82 to 105. Certain amino acid substitutions can be made to provide one or more of the variant antibodies described herein.

[0111] Also provided are anti-TCR delta variable region 1 (anti-V51) antibodies or antigen-binding fragments thereof, comprising: VHCDR1 comprising or consisting of an amino acid sequence selected from the group consisting of SEQ ID NOs: 51 and 52; VHCDR2 comprising or consisting of the amino acid sequence of SEQ ID NO: 53; and A heavy chain variable region comprising a VHCDR3 comprising or consisting of an amino acid sequence selected from the group consisting of SEQ ID NOs: 55 to 77, and VLCDR1 comprising or consisting of the amino acid sequence of SEQ ID NO: 79; VLCDR2 comprising or consisting of the amino acid sequence of SEQ ID NO: 80; and A light chain variable region comprising a VLCDR3 comprising or consisting of an amino acid sequence selected from the group consisting of SEQ ID NOs: 82 to 104. Certain amino acid substitutions can be made to provide one or more of the variant antibodies described herein.

[0112] Also provided are anti-TCR delta variable region 1 (anti-V51) antibodies or antigen-binding fragments thereof, comprising: VHCDR1 comprising or consisting of an amino acid sequence selected from the group consisting of SEQ ID NOs: 51 and 52; VHCDR2 comprising or consisting of the amino acid sequence of SEQ ID NO: 53; and a heavy chain variable region comprising a VHCDR3 comprising or consisting of an amino acid sequence selected from the group consisting of SEQ ID NOs: 58, 60, 61, 62, 65, 66, 68, 74, 76, and 77; and VLCDR1 comprising or consisting of the amino acid sequence of SEQ ID NO: 79; VLCDR2 comprising or consisting of the amino acid sequence of SEQ ID NO: 80; and A light chain variable region comprising a VLCDR3 comprising or consisting of an amino acid sequence selected from the group consisting of SEQ ID NOs: 85, 87, 88, 89, 92, 93, 95, 101, 103, and 104.

[0113] Certain amino acid substitutions can be made to provide one or more of the variant antibodies described herein.

[0114] Also provided are anti-TCR delta variable region 1 (anti-V51) antibodies or antigen-binding fragments thereof, comprising: a) VHCDR1, VHCDR2, and VHCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 51, 53, and 55, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 79, 80, and 82, respectively; b) VHCDR1, VHCDR2, and VHCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 51, 53, and 56, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 79, 80, and 83, respectively; c) VHCDR1, VHCDR2, and VHCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 51, 53, and 57, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 79, 80, and 84, respectively; d) VHCDR1, VHCDR2, and VHCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 51, 53, and 58, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 79, 80, and 85, respectively; e) VHCDR1, VHCDR2, and VHCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 51, 53, and 59, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 79, 80, and 86, respectively; f) VHCDR1, VHCDR2, and VHCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 51, 53, and 60, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 79, 80, and 87, respectively; g) VHCDR1, VHCDR2, and VHCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 52, 53, and 61, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 79, 80, and 88, respectively; h) VHCDR1, VHCDR2, and VHCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 51, 53, and 62, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 79, 80, and 89, respectively; i) VHCDR1, VHCDR2, and VHCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 51, 53, and 63, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 79, 80, and 90, respectively; j) VHCDR1, VHCDR2, and VHCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 51, 53, and 64, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 79, 80, and 91, respectively; k) VHCDR1, VHCDR2, and VHCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 51, 53, and 65, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 79, 80, and 92, respectively; l) VHCDR1, VHCDR2, and VHCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 52, 53, and 66, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 79, 80, and 93, respectively; m) VHCDR1, VHCDR2, and VHCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 51, 53, and 67, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 79, 80, and 94, respectively; n) VHCDR1, VHCDR2, and VHCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 51, 53, and 68, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 79, 80, and 95, respectively; o) VHCDR1, VHCDR2, and VHCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 51, 53, and 69, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 79, 80, and 96, respectively; p) VHCDR1, VHCDR2, and VHCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 51, 53, and 70, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 79, 80, and 97, respectively; q) VHCDR1, VHCDR2, and VHCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 51, 53, and 71, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 79, 80, and 98, respectively; r) VHCDR1, VHCDR2, and VHCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 51, 53, and 72, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 79, 80, and 99, respectively; s) VHCDR1, VHCDR2, and VHCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 51, 53, and 73, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 79, 80, and 100, respectively; t) VHCDR1, VHCDR2, and VHCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 52, 53, and 74, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 79, 80, and 101, respectively; u) VHCDR1, VHCDR2, and VHCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 51, 53, and 75, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 79, 80, and 102, respectively; v) VHCDR1, VHCDR2, and VHCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 51, 53, and 76, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 79, 80, and 103, respectively; w) VHCDR1, VHCDR2, and VHCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 51, 53, and 77, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 79, 80, and 104, respectively; or x) VHCDR1, VHCDR2, and VHCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 51, 53, and 78, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising or consisting of the amino acid sequences of SEQ ID NOs: 79, 80, and 105, respectively.

[0115] The anti-V51 antibody or antigen-binding fragment thereof may comprise a κ light chain variable sequence (or comprise a variable light chain derived from a κ light chain variable sequence), wherein the residue at position 74 of the κ light chain variable sequence according to the IMGT numbering system is not a serine, e.g., a non-human germline residue at position 74 and / or a non-polar residue, e.g., the residue at position 74 is a leucine residue.

[0116] Further embodiments are provided below.

[0117] ADT1-4-105 and its fragments and variants Certain embodiments relate to the antibody ADT1-4-105 and fragments and variants thereof.

[0118] For example, in some embodiments, an antibody or antigen-binding fragment or variant thereof is provided that comprises a heavy chain variable region comprising a VH CDR3 comprising an amino acid sequence having at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 55, and / or a light chain variable region comprising a VL CDR3 comprising an amino acid sequence having at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 82. In one embodiment, an antibody or antigen-binding fragment or variant thereof is provided, comprising a heavy chain variable region comprising a VHCDR3 comprising an amino acid sequence having at least 90% identity to the amino acid sequence of SEQ ID NO: 55, and / or a light chain variable region comprising a VLCDR3 comprising an amino acid sequence having at least 90% identity to the amino acid sequence of SEQ ID NO: 82. In one embodiment, an antibody or antigen-binding fragment or variant thereof is provided, comprising a heavy chain variable region comprising a VHCDR3 comprising the amino acid sequence of SEQ ID NO: 55, and / or a light chain variable region comprising a VLCDR3 comprising the amino acid sequence of SEQ ID NO: 82.

[0119] Amino acid substitutions can be made to provide variant antibodies derived from ADT1-4-105, for example, an antibody or antigen-binding fragment or variant thereof is provided that comprises a heavy chain variable region comprising a VH CDR3 comprising the amino acid sequence of SEQ ID NO: 55, optionally containing one or two amino acid substitutions, and / or a light chain variable region comprising a VL CDR3 comprising the amino acid sequence of SEQ ID NO: 82, optionally containing one or two amino acid substitutions. The amino acid substitutions can be conservative amino acid substitutions.

[0120] In some embodiments, an antibody or antigen-binding fragment or variant thereof is provided that comprises: VHCDR1 comprising at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 51, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 53 a heavy chain variable region comprising a VHCDR2 that comprises at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity, and a VHCDR3 that comprises at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 55; and / or VLCDR1 comprising at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 79, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93% identity to the amino acid sequence of SEQ ID NO: 80 , at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 82, and a VLCDR3 that comprises at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 82.

[0121] In one embodiment, an antibody or antigen-binding fragment or variant thereof is provided that comprises: a heavy chain variable region comprising a VHCDR1 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 51, a VHCDR2 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 53, and a VHCDR3 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 55; and / or A light chain variable region comprising VLCDR1 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 79, VLCDR2 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 80, and VLCDR3 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 82.

[0122] In one embodiment, an antibody or antigen-binding fragment or variant thereof is provided that comprises: a heavy chain variable region comprising a VHCDR1 comprising the amino acid sequence of SEQ ID NO: 51, a VHCDR2 comprising the amino acid sequence of SEQ ID NO: 53, and a VHCDR3 comprising the amino acid sequence of SEQ ID NO: 55; and A light chain variable region comprising VLCDR1 comprising the amino acid sequence of SEQ ID NO:79, VLCDR2 comprising the amino acid sequence of SEQ ID NO:80, and VLCDR3 comprising the amino acid sequence of SEQ ID NO:82.

[0123] Amino acid substitutions can be made to provide variant antibodies derived from ADT1-4-105, for example, to provide antibodies or antigen-binding fragments or variants thereof comprising: a heavy chain variable region comprising a VHCDR1 comprising the amino acid sequence of SEQ ID NO: 51, optionally containing one or two amino acid substitutions, a VHCDR2 comprising the amino acid sequence of SEQ ID NO: 53, optionally containing one or two amino acid substitutions, and a VHCDR3 comprising the amino acid sequence of SEQ ID NO: 55, optionally containing one or two amino acid substitutions; and / or A light chain variable region comprising VLCDR1 comprising the amino acid sequence of SEQ ID NO: 79, optionally containing one or two amino acid substitutions, VLCDR2 comprising the amino acid sequence of SEQ ID NO: 80, optionally containing one or two amino acid substitutions, and VLCDR3 comprising the amino acid sequence of SEQ ID NO: 82, optionally containing one or two amino acid substitutions. The amino acid substitutions may be conservative amino acid substitutions.

[0124] Alternatively, the antibody may consist of the specified sequence (with or without amino acid substitutions).

[0125] ADT1-4-107 and its fragments and variants Particular embodiments relate to the antibody ADT1-4-107 and fragments and variants thereof.

[0126] For example, in some embodiments, an antibody or antigen-binding fragment or variant thereof is provided that comprises a heavy chain variable region comprising a VH CDR3 comprising an amino acid sequence having at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 56, and / or a light chain variable region comprising a VL CDR3 comprising an amino acid sequence having at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 83. In one embodiment, an antibody or antigen-binding fragment or variant thereof is provided, comprising a heavy chain variable region comprising a VHCDR3 comprising an amino acid sequence having at least 90% identity to the amino acid sequence of SEQ ID NO: 56, and / or a light chain variable region comprising a VLCDR3 comprising an amino acid sequence having at least 90% identity to the amino acid sequence of SEQ ID NO: 83. In one embodiment, an antibody or antigen-binding fragment or variant thereof is provided, comprising a heavy chain variable region comprising a VHCDR3 comprising the amino acid sequence of SEQ ID NO: 56, and / or a light chain variable region comprising a VLCDR3 comprising the amino acid sequence of SEQ ID NO: 83.

[0127] Amino acid substitutions can be made to provide variant antibodies derived from ADT1-4-107, for example, an antibody or antigen-binding fragment or variant thereof is provided that comprises a heavy chain variable region comprising a VH CDR3 comprising the amino acid sequence of SEQ ID NO: 56, optionally containing one or two amino acid substitutions, and / or a light chain variable region comprising a VL CDR3 comprising the amino acid sequence of SEQ ID NO: 83, optionally containing one or two amino acid substitutions. The amino acid substitutions can be conservative amino acid substitutions.

[0128] In some embodiments, an antibody or antigen-binding fragment or variant thereof is provided that comprises: VHCDR1 comprising at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 51, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 53 a heavy chain variable region comprising a VHCDR2 that comprises at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity, and a VHCDR3 that comprises at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 56; and / or VLCDR1 comprising at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 79, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93% identity to the amino acid sequence of SEQ ID NO: 80 , at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 83, and a VLCDR3 that comprises at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 83.

[0129] In one embodiment, an antibody or antigen-binding fragment or variant thereof is provided that comprises: a heavy chain variable region comprising a VHCDR1 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 51, a VHCDR2 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 53, and a VHCDR3 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 56; and / or A light chain variable region comprising VLCDR1 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 79, VLCDR2 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 80, and VLCDR3 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 83.

[0130] In one embodiment, an antibody or antigen-binding fragment or variant thereof is provided that comprises: a heavy chain variable region comprising a VHCDR1 comprising the amino acid sequence of SEQ ID NO: 51, a VHCDR2 comprising the amino acid sequence of SEQ ID NO: 53, and a VHCDR3 comprising the amino acid sequence of SEQ ID NO: 56; and A light chain variable region comprising VLCDR1 comprising the amino acid sequence of SEQ ID NO: 79, VLCDR2 comprising the amino acid sequence of SEQ ID NO: 80, and VLCDR3 comprising the amino acid sequence of SEQ ID NO: 83.

[0131] Amino acid substitutions can be made to provide variant antibodies derived from ADT1-4-107, for example, to provide antibodies or antigen-binding fragments or variants thereof comprising: a heavy chain variable region comprising a VHCDR1 comprising the amino acid sequence of SEQ ID NO: 51, optionally containing one or two amino acid substitutions, a VHCDR2 comprising the amino acid sequence of SEQ ID NO: 53, optionally containing one or two amino acid substitutions, and a VHCDR3 comprising the amino acid sequence of SEQ ID NO: 56, optionally containing one or two amino acid substitutions; and / or A light chain variable region comprising VLCDR1 comprising the amino acid sequence of SEQ ID NO: 79, optionally containing one or two amino acid substitutions, VLCDR2 comprising the amino acid sequence of SEQ ID NO: 80, optionally containing one or two amino acid substitutions, and VLCDR3 comprising the amino acid sequence of SEQ ID NO: 83, optionally containing one or two amino acid substitutions. The amino acid substitutions may be conservative amino acid substitutions.

[0132] Alternatively, the antibody may consist of the specified sequence (with or without amino acid substitutions).

[0133] ADT1-4-110 and its fragments and variants Particular embodiments relate to the antibody ADT1-4-110 and fragments and variants thereof.

[0134] For example, in some embodiments, an antibody or antigen-binding fragment or variant thereof is provided that comprises a heavy chain variable region comprising a VH CDR3 comprising an amino acid sequence having at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 57, and / or a light chain variable region comprising a VL CDR3 comprising an amino acid sequence having at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 84. In one embodiment, an antibody or antigen-binding fragment or variant thereof is provided, comprising a heavy chain variable region comprising a VHCDR3 comprising an amino acid sequence having at least 90% identity to the amino acid sequence of SEQ ID NO: 57, and / or a light chain variable region comprising a VLCDR3 comprising an amino acid sequence having at least 90% identity to the amino acid sequence of SEQ ID NO: 84. In one embodiment, an antibody or antigen-binding fragment or variant thereof is provided, comprising a heavy chain variable region comprising a VHCDR3 comprising the amino acid sequence of SEQ ID NO: 57, and / or a light chain variable region comprising a VLCDR3 comprising the amino acid sequence of SEQ ID NO: 84.

[0135] Amino acid substitutions can be made to provide variant antibodies derived from ADT1-4-110, for example, an antibody or antigen-binding fragment or variant thereof is provided that comprises a heavy chain variable region comprising a VH CDR3 comprising the amino acid sequence of SEQ ID NO: 57, optionally containing one or two amino acid substitutions, and / or a light chain variable region comprising a VL CDR3 comprising the amino acid sequence of SEQ ID NO: 84, optionally containing one or two amino acid substitutions. The amino acid substitutions can be conservative amino acid substitutions.

[0136] In some embodiments, an antibody or antigen-binding fragment or variant thereof is provided that comprises: VHCDR1 comprising at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 51, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 53 a heavy chain variable region comprising a VHCDR2 that comprises at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity, and a VHCDR3 that comprises at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 57; and / or VLCDR1 comprising at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 79, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93% identity to the amino acid sequence of SEQ ID NO: 80 , a VLCDR2 that comprises at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 84, and a VLCDR3 that comprises at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 84.

[0137] In one embodiment, an antibody or antigen-binding fragment or variant thereof is provided that comprises: a heavy chain variable region comprising a VHCDR1 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 51, a VHCDR2 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 53, and a VHCDR3 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 57; and / or A light chain variable region comprising VLCDR1 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 79, VLCDR2 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 80, and VLCDR3 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 84.

[0138] In one embodiment, an antibody or antigen-binding fragment or variant thereof is provided that comprises: a heavy chain variable region comprising a VHCDR1 comprising the amino acid sequence of SEQ ID NO: 51, a VHCDR2 comprising the amino acid sequence of SEQ ID NO: 53, and a VHCDR3 comprising the amino acid sequence of SEQ ID NO: 57; and A light chain variable region comprising VLCDR1 comprising the amino acid sequence of SEQ ID NO:79, VLCDR2 comprising the amino acid sequence of SEQ ID NO:80, and VLCDR3 comprising the amino acid sequence of SEQ ID NO:84.

[0139] Amino acid substitutions can be made to provide variant antibodies derived from ADT1-4-110, for example, to provide antibodies or antigen-binding fragments or variants thereof comprising: a heavy chain variable region comprising a VHCDR1 comprising the amino acid sequence of SEQ ID NO: 51, optionally containing one or two amino acid substitutions, a VHCDR2 comprising the amino acid sequence of SEQ ID NO: 53, optionally containing one or two amino acid substitutions, and a VHCDR3 comprising the amino acid sequence of SEQ ID NO: 57, optionally containing one or two amino acid substitutions; and / or A light chain variable region comprising: VLCDR1 comprising the amino acid sequence of SEQ ID NO: 79, optionally containing one or two amino acid substitutions; VLCDR2 comprising the amino acid sequence of SEQ ID NO: 80, optionally containing one or two amino acid substitutions; and VLCDR3 comprising the amino acid sequence of SEQ ID NO: 84, optionally containing one or two amino acid substitutions. The amino acid substitutions may be conservative amino acid substitutions.

[0140] Alternatively, the antibody may consist of the specified sequence (with or without amino acid substitutions).

[0141] ADT1-4-112 and its fragments and variants Particular embodiments relate to the antibody ADT1-4-112 and fragments and variants thereof.

[0142] For example, in some embodiments, an antibody or antigen-binding fragment or variant thereof is provided that comprises a heavy chain variable region comprising a VH CDR3 comprising an amino acid sequence having at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 58, and / or a light chain variable region comprising a VL CDR3 comprising an amino acid sequence having at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 85. In one embodiment, an antibody or antigen-binding fragment or variant thereof is provided, comprising a heavy chain variable region comprising a VHCDR3 comprising an amino acid sequence having at least 90% identity to the amino acid sequence of SEQ ID NO: 58, and / or a light chain variable region comprising a VLCDR3 comprising an amino acid sequence having at least 90% identity to the amino acid sequence of SEQ ID NO: 85. In one embodiment, an antibody or antigen-binding fragment or variant thereof is provided, comprising a heavy chain variable region comprising a VHCDR3 comprising the amino acid sequence of SEQ ID NO: 58, and / or a light chain variable region comprising a VLCDR3 comprising the amino acid sequence of SEQ ID NO: 85.

[0143] Amino acid substitutions can be made to provide variant antibodies derived from ADT1-4-112, for example, an antibody or antigen-binding fragment or variant thereof is provided that comprises a heavy chain variable region comprising a VH CDR3 comprising the amino acid sequence of SEQ ID NO: 58, optionally containing one or two amino acid substitutions, and / or a light chain variable region comprising a VL CDR3 comprising the amino acid sequence of SEQ ID NO: 85, optionally containing one or two amino acid substitutions. The amino acid substitutions can be conservative amino acid substitutions.

[0144] In some embodiments, an antibody or antigen-binding fragment or variant thereof is provided that comprises: VHCDR1 comprising at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 51, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 53 a heavy chain variable region comprising a VHCDR2 that comprises at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity, and a VHCDR3 that comprises at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 58; and / or VLCDR1 comprising at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 79, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93% identity to the amino acid sequence of SEQ ID NO: 80 , a VLCDR2 that comprises at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 85, and a VLCDR3 that comprises at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 85.

[0145] In one embodiment, an antibody or antigen-binding fragment or variant thereof is provided that comprises: a heavy chain variable region comprising a VHCDR1 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 51, a VHCDR2 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 53, and a VHCDR3 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 58; and / or A light chain variable region comprising VLCDR1 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 79, VLCDR2 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 80, and VLCDR3 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 85.

[0146] In one embodiment, an antibody or antigen-binding fragment or variant thereof is provided that comprises: a heavy chain variable region comprising a VHCDR1 comprising the amino acid sequence of SEQ ID NO: 51, a VHCDR2 comprising the amino acid sequence of SEQ ID NO: 53, and a VHCDR3 comprising the amino acid sequence of SEQ ID NO: 58; and A light chain variable region comprising VLCDR1 comprising the amino acid sequence of SEQ ID NO: 79, VLCDR2 comprising the amino acid sequence of SEQ ID NO: 80, and VLCDR3 comprising the amino acid sequence of SEQ ID NO: 85.

[0147] Amino acid substitutions can be made to provide variant antibodies derived from ADT1-4-112, for example, to provide antibodies or antigen-binding fragments or variants thereof comprising: a heavy chain variable region comprising a VHCDR1 comprising the amino acid sequence of SEQ ID NO: 51, optionally containing one or two amino acid substitutions, a VHCDR2 comprising the amino acid sequence of SEQ ID NO: 53, optionally containing one or two amino acid substitutions, and a VHCDR3 comprising the amino acid sequence of SEQ ID NO: 58, optionally containing one or two amino acid substitutions; and / or A light chain variable region comprising: VLCDR1 comprising the amino acid sequence of SEQ ID NO: 79, optionally containing one or two amino acid substitutions; VLCDR2 comprising the amino acid sequence of SEQ ID NO: 80, optionally containing one or two amino acid substitutions; and VLCDR3 comprising the amino acid sequence of SEQ ID NO: 85, optionally containing one or two amino acid substitutions. The amino acid substitutions may be conservative amino acid substitutions.

[0148] Alternatively, the antibody may consist of the specified sequence (with or without amino acid substitutions).

[0149] ADT1-4-117 and its fragments and variants Particular embodiments relate to the antibody ADT1-4-117 and fragments and variants thereof.

[0150] For example, in some embodiments, an antibody or antigen-binding fragment or variant thereof is provided that comprises a heavy chain variable region comprising a VH CDR3 comprising an amino acid sequence having at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 59, and / or a light chain variable region comprising a VL CDR3 comprising an amino acid sequence having at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 86. In one embodiment, an antibody or antigen-binding fragment or variant thereof is provided, comprising a heavy chain variable region comprising a VHCDR3 comprising an amino acid sequence having at least 90% identity to the amino acid sequence of SEQ ID NO: 59, and / or a light chain variable region comprising a VLCDR3 comprising an amino acid sequence having at least 90% identity to the amino acid sequence of SEQ ID NO: 86. In one embodiment, an antibody or antigen-binding fragment or variant thereof is provided, comprising a heavy chain variable region comprising a VHCDR3 comprising the amino acid sequence of SEQ ID NO: 59, and / or a light chain variable region comprising a VLCDR3 comprising the amino acid sequence of SEQ ID NO: 86.

[0151] Amino acid substitutions can be made to provide variant antibodies derived from ADT1-4-117, for example, an antibody or antigen-binding fragment or variant thereof is provided that comprises a heavy chain variable region comprising a VH CDR3 comprising the amino acid sequence of SEQ ID NO: 59, optionally containing one or two amino acid substitutions, and / or a light chain variable region comprising a VL CDR3 comprising the amino acid sequence of SEQ ID NO: 86, optionally containing one or two amino acid substitutions. The amino acid substitutions can be conservative amino acid substitutions.

[0152] In some embodiments, an antibody or antigen-binding fragment or variant thereof is provided that comprises: VHCDR1 comprising at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 51, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 53 a heavy chain variable region comprising a VHCDR2 that comprises at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity, and a VHCDR3 that comprises at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 59; and / or VLCDR1 comprising at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 79, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93% identity to the amino acid sequence of SEQ ID NO: 80 , at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 86, and a VLCDR3 that comprises at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to the amino acid sequence of SEQ ID NO: 86.

[0153] In one embodiment, an antibody or antigen-binding fragment or variant thereof is provided that comprises: a heavy chain variable region comprising a VHCDR1 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 51, a VHCDR2 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 53, and a VHCDR3 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 59; and / or A light chain variable region comprising VLCDR1 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 79, VLCDR2 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 80, and VLCDR3 comprising at least 90% identity to the amino acid sequence of SEQ ID NO: 86.

[0154] In one embodiment, an antibody or antigen-binding fragment or variant thereof is provided that comprises: a heavy chain variable region comprising a VHCDR1 comprising the amino acid sequence of SEQ ID NO: 51, a VHCDR2 comprising the amino acid sequence of SEQ ID NO: 53, and a VHCDR3 comprising the amino acid sequence of SEQ ID NO: 59; and A light chain variable region comprising VLCDR1 comprising the amino acid sequence of SEQ ID NO:79, VLCDR2 comprising the amino acid sequence of SEQ ID NO:80, and VLCDR3 comprising the amino acid sequence of SEQ ID NO:86.

[0155] Amino acid substitutions can be made to provide variant antibodies derived from ADT1-4-117, for example, to provide antibodies or antigen-binding fragments or variants thereof comprising: a heavy chain variable region comprising a VHCDR1 comprising the amino acid sequence of SEQ ID NO: 51, optionally containing one or two amino acid substitutions, a VHCDR2 comprising the amino acid sequence of SEQ ID NO: 53, optionally containing one or two amino acid substitutions, and a VHCDR3 comprising the amino acid sequence of SEQ ID NO: 59, optional...

Claims

1. An anti-TCRδ variable domain 1 (anti-Vδ1) antibody or antigen-binding fragment thereof comprising a heavy chain variable domain and a light chain variable domain, the antibody or antigen-binding fragment thereof comprising: a. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 68, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 95, respectively; b. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 55, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 82, respectively; c. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 56, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 83, respectively; d. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 57, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 84, respectively; e. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 58, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 85, respectively; f. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 59, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 86, respectively; g. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 60, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 87, respectively; h. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 52, 53, and 61, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 88, respectively; i. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 62, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 89, respectively; j. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 63, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 90, respectively; k. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 64, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 91, respectively; l. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 65, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 92, respectively; m. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 52, 53, and 66, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 93, respectively; n. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 67, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 94, respectively; o. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 69, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 96, respectively; p. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 70, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 97, respectively; q. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 71, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 98, respectively; r. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 72, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 99, respectively; s. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 73, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 100, respectively; t. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 52, 53, and 74, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 101, respectively; VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 75, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 102, respectively; v. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 76, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 103, respectively; w. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 77, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 104, respectively; x. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 78, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 105, respectively; y. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 130, 131, and 133, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 144, 145, and 147, respectively; z. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 130, 131, and 134, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 144, 145, and 148, respectively; aa. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 130, 131, and 135, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 144, 145, and 149, respectively; bb. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 130, 131, and 136, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 144, 145, and 150, respectively; cc. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 130, 131, and 137, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 144, 145, and 151, respectively; dd. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 130, 131, and 138, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 144, 145, and 152, respectively; VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 130, 131, and 139, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 144, 145, and 153, respectively; ff. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 130, 131, and 140, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 144, 145, and 154, respectively; VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 130, 131, and 141, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 144, 145, and 155, respectively; hh. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 130, 131, and 142, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 144, 145, and 156, respectively; or ii. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 130, 131, and 143, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 144, 145, and 157, respectively; An antibody or an antigen-binding fragment thereof.

2. The anti-TCRδ variable domain 1 (anti-Vδ1) antibody or antigen-binding fragment thereof according to claim 1, comprising a heavy chain variable domain and a light chain variable domain, the antibody or antigen-binding fragment thereof comprising: a. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 68, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 95, respectively; b. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 58, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 85, respectively; c. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 60, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 87, respectively; d. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 52, 53, and 61, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 88, respectively; e. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 62, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 89, respectively; f. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 65, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 92, respectively; g. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 52, 53, and 66, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 93, respectively; h. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 52, 53, and 74, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 101, respectively; i. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 76, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 103, respectively; j. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 77, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 104, respectively; k. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 51, 53, and 78, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 79, 80, and 105, respectively; l. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 130, 131, and 138, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 144, 145, and 152, respectively; m. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 130, 131, and 142, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 144, 145, and 156, respectively; or n. VHCDR1, VHCDR2, and VHCDR3 comprising the amino acid sequences of SEQ ID NOs: 130, 131, and 143, respectively, and VLCDR1, VLCDR2, and VLCDR3 comprising the amino acid sequences of SEQ ID NOs: 144, 145, and 157, respectively; An antibody or an antigen-binding fragment thereof.

3. a. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 15, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 40; b. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:2, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:27; c. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:3, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:28; d. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:4, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:29; e. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:5, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:30; f. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:6, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:31; g. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:7, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:32; h. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:8, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:33; i. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:9, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:34; j. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 10, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 35; k. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 11, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 36; l. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 12, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 37; m. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 13, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 38; n. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 14, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 39; o. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 16, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 41; p. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 17, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 42; q. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 18, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 43; r. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 19, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 44; s. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 20, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 45; a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 21, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 46; a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:22, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:47; v. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:23, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:48; w. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:24, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:49; x. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:25, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:50; y. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 107, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 119; z. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 108, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 120; aa. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 109, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 121; bb. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 110, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 122; cc. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 111, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 123; dd. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 112, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 124; a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 113, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 125; ff. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 114, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 126; a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 115, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 127; hh. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 116, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 128; or ii. The anti-V51 antibody or antigen-binding fragment thereof of claim 1 or 2, comprising a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 117, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:

129.

4. The anti-TCRδ variable domain 1 (anti-Vδ1) antibody or antigen-binding fragment thereof according to claim 3, comprising a heavy chain variable domain and a light chain variable domain, wherein the antibody or antigen-binding fragment thereof comprises: a. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 15, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 40; b. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:5, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:30; c. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:7, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:32; d. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:8, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:33; e. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:9, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:34; f. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 12, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 37; g. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 13, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 38; h. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 21, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 46; i. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 23, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 48; j. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:24, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:49; k. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:25, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:50; l. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 112, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 124; m. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 116, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 128; or n. A VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 117, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 129; An antibody or an antigen-binding fragment thereof. Claim 5: a. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 15, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 40; b. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:2, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:27; c. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:3, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:28; d. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:4, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:29; e. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:5, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:30; f. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:6, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:31; g. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:7, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:32; h. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:8, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:33; i. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:9, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:34; j. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 10, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 35; k. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 11, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 36; l. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 12, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 37; m. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 13, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 38; n. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 14, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 39; o. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 16, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 41; p. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 17, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 42; q. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 18, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 43; r. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 19, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 44; s. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 20, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 45; a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 21, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 46; a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:22, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:47; v. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:23, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:48; w. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:24, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:49; x. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:25, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:50; y. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 107, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 119; z. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 108, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 120; aa. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 109, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 121; bb. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 110, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 122; cc. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 111, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 123; dd. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 112, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 124; a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 113, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 125; ff. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 114, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 126; a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 115, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 127; hh. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 116, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 128; or ii. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 117, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 129; Anti-TCRδ variable region 1 (anti-Vδ1) antibody or antigen-binding fragment thereof. Claim 6: A VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 15, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 40; b. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:5, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:30; c. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:7, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:32; d. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:8, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:33; e. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:9, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:34; f. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 12, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 37; g. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 13, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 38; h. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 21, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 46; i. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 23, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 48; j. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:24, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:49; k. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:25, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO:50; l. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 112, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 124; m. a VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 116, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 128; or n. A VH comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 117, and a VL comprising an amino acid sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% sequence identity to SEQ ID NO: 129; An anti-Vδ1 antibody or an antigen-binding fragment thereof according to claim 5.

7. An anti-TCRδ variable region 1 (anti-Vδ1) antibody or an antigen-binding fragment thereof, comprising a VH having the amino acid sequence of SEQ ID NO: 15 and a VL having the amino acid sequence of SEQ ID NO:

40.

8. An anti-TCRδ variable region 1 (anti-Vδ1) antibody or an antigen-binding fragment thereof, comprising a VH having the amino acid sequence of SEQ ID NO: 23 and a VL having the amino acid sequence of SEQ ID NO:

48.

9. An anti-TCRδ variable region 1 (anti-Vδ1) antibody or an antigen-binding fragment thereof, comprising a VH having the amino acid sequence of SEQ ID NO:5 and a VL having the amino acid sequence of SEQ ID NO:

30.

10. 10. The anti-Vδ1 antibody or antigen-binding fragment thereof of any one of claims 1 to 9, wherein the antibody or antigen-binding fragment thereof comprises an amino acid residue other than serine at position 74 according to the IMGT numbering system of the kappa light chain variable sequence, and optionally, the residue at position 74 according to the IMGT numbering system is a leucine residue.

11. An anti-TCRδ variable region 1 (anti-Vδ1) antibody or antigen-binding fragment thereof, comprising: a. GDSVSSKSX １ A (SEQ ID NO: 158); b. a HCDR2 sequence comprising the sequence of SEQ ID NO:53; C. X ２ WX ３ X ４ X ５ X ６ D.X. ７ HCDR3 sequence comprising the sequence of (SEQ ID NO: 162), wherein said HCDR3 sequence is not SEQ ID NO: 54; d. an LCDR1 sequence comprising the sequence of SEQ ID NO:79; e. a LCDR2 sequence comprising the sequence of SEQ ID NO: 80; and f. QQX ８ YX ９ X １０ X １１ X １２ X １３ T (SEQ ID NO: 166), wherein said LCDR3 sequence is not SEQ ID NO: 81; X １ ~X １３ each of which is a naturally occurring amino acid, or or the antibody or antigen-binding fragment thereof, a. a HCDR1 sequence comprising the sequence of SEQ ID NO: 130; b. a HCDR2 sequence comprising the sequence of SEQ ID NO: 131; C. X １ X ２ YX ３ X ４ an HCDR3 sequence comprising the sequence of AFDI, wherein said HCDR3 sequence is not SEQ ID NO: 132; d. an LCDR1 sequence comprising the sequence of SEQ ID NO: 144; e. a LCDR2 sequence comprising the sequence of SEQ ID NO: 145; and f. QQX ５ X ６ X ７ X ８ LX ９ T, wherein said LCDR3 sequence is not SEQ ID NO: 146; X １ ~X ９ Each of the following is a naturally occurring amino acid:

12. An anti-TCRδ variable region 1 (anti-Vδ1) antibody or antigen-binding fragment thereof, wherein the anti-Vδ1 antibody or antigen-binding fragment thereof is an affinity matured variant of a parent anti-Vδ1 antibody or antigen-binding fragment thereof, the parent anti-Vδ1 antibody or antigen-binding fragment thereof comprising: a. a VH comprising the amino acid sequence of SEQ ID NO: 1 and a VL comprising the amino acid sequence of SEQ ID NO: 26; b. a VH comprising the amino acid sequence of SEQ ID NO: 106 and a VL comprising the amino acid sequence of SEQ ID NO: 118; c. a VH comprising the amino acid sequence of SEQ ID NO:273 and a VL comprising the amino acid sequence of SEQ ID NO:282; d. a VH comprising the amino acid sequence of SEQ ID NO:274 and a VL comprising the amino acid sequence of SEQ ID NO:283; e. a VH comprising the amino acid sequence of SEQ ID NO:275 and a VL comprising the amino acid sequence of SEQ ID NO:284; f. a VH comprising the amino acid sequence of SEQ ID NO:276 and a VL comprising the amino acid sequence of SEQ ID NO:285; g. a VH comprising the amino acid sequence of SEQ ID NO:277 and a VL comprising the amino acid sequence of SEQ ID NO:286; h. a VH comprising the amino acid sequence of SEQ ID NO:278 and a VL comprising the amino acid sequence of SEQ ID NO:287; i. a VH comprising the amino acid sequence of SEQ ID NO:279 and a VL comprising the amino acid sequence of SEQ ID NO:288; j. a VH comprising the amino acid sequence of SEQ ID NO:280 and a VL comprising the amino acid sequence of SEQ ID NO:289; k. a VH comprising the amino acid sequence of SEQ ID NO: 281 and a VL comprising the amino acid sequence of SEQ ID NO: 290; or l. A VH comprising the amino acid sequence of SEQ ID NO: 312 and a VL comprising the amino acid sequence of SEQ ID NO: 313; Optionally, the affinity matured antibody has at least 20%, at least 30%, at least 40%, at least 50%, at least 100%, at least 500%, or more preferably at least about 1000% greater affinity for binding to the variable δ1 (Vδ1) chain of the γδ T cell receptor (TCR) than the parent antibody, e.g., as measured by Kd; said affinity matured anti-V51 antibody or antigen-binding fragment thereof comprises VH and VL sequences that are at least 80%, at least 90%, at least 95%, or at least 96% identical to the corresponding parent VH and VL sequences; and / or The anti-TCRδ variable region 1 (anti-Vδ1) antibody or antigen-binding fragment thereof, wherein the affinity matured anti-Vδ1 antibody or antigen-binding fragment thereof comprises up to 20, such as up to 15, such as up to 10 amino acid substitutions compared to the parent antibody sequence.

13. An anti-Vδ1 antibody or antigen-binding fragment, comprising: a. a first target epitope, the first target epitope being an epitope of the variable δ1 (Vδ1) chain of the γδ T cell receptor (TCR); and b. a multispecific antibody that specifically binds to a second target epitope; The multispecific antibody comprises the sequences of SEQ ID NO:393; SEQ ID NO:388; SEQ ID NO:315; SEQ ID NO:316; SEQ ID NO:378; SEQ ID NO:379; SEQ ID NO:380; SEQ ID NO:382; SEQ ID NO:383; SEQ ID NO:384; SEQ ID NO:393; SEQ ID NO:396; SEQ ID NO:398; SEQ ID NO:399; SEQ ID NO:401; SEQ ID NO:403; SEQ ID NO:405; SEQ ID NO:407; SEQ ID NO:409; SEQ ID NO:411; SEQ ID NO:414 and SEQ ID NO:415; SEQ ID NO:414 and SEQ ID NO:416; SEQ ID NO:414 and SEQ ID NO:419; SEQ ID NO:414 and SEQ ID NO:418; SEQ ID NO:504 and SEQ ID NO:415; SEQ ID NO:504 and SEQ ID NO:416; SEQ ID NO:504 and SEQ ID NO:419; SEQ ID NO:504 and SEQ ID NO:418; SEQ ID NO:505 and SEQ ID NO:415; SEQ ID NO:505 and SEQ ID NO:416; SEQ ID NO:505 and SEQ ID NO:419; SEQ ID NO:505 and SEQ ID NO:418; SEQ ID NO:421 and SEQ ID NO:422; SEQ ID NO:504 and SEQ ID NO:422; SEQ ID NO: the anti-Vδ1 antibody or antigen-binding fragment comprising SEQ ID NO:423 and SEQ ID NO:424; SEQ ID NO:425 and SEQ ID NO:426; SEQ ID NO:421 and SEQ ID NO:437; SEQ ID NO:504 and SEQ ID NO:437; SEQ ID NO:423 and SEQ ID NO:427; SEQ ID NO:425 and SEQ ID NO:428; SEQ ID NO:421 and SEQ ID NO:429; SEQ ID NO:504 and SEQ ID NO:429; SEQ ID NO:423 and SEQ ID NO:430; SEQ ID NO:414 and SEQ ID NO:431; SEQ ID NO:414 and SEQ ID NO:433; SEQ ID NO:414 and SEQ ID NO:434; SEQ ID NO:414 and SEQ ID NO:435; SEQ ID NO:504 and SEQ ID NO:431; SEQ ID NO:504 and SEQ ID NO:433; SEQ ID NO:504 and SEQ ID NO:434; SEQ ID NO:504 and SEQ ID NO:435; SEQ ID NO:505 and SEQ ID NO:431; SEQ ID NO:505 and SEQ ID NO:433; SEQ ID NO:505 and SEQ ID NO:434; SEQ ID NO:505 and SEQ ID NO:435; SEQ ID NO:438 and SEQ ID NO:417; or SEQ ID NO:439 and SEQ ID NO:

420. Claim 14: a. the multispecific antibody causes depletion of less than about 30%, or less than about 20%, or less than about 10% of the viable V51+ T cell population by ADCC and / or CDC; and / or b. the antibody or antigen-binding fragment thereof binds to human TRVD1 with a K of less than about 10 nM, optionally, the antibody or antigen-binding fragment thereof binds to cyno TRVD1 with a K of less than about 100 nM; An anti-TCRδ variable region 1 (anti-Vδ1) antibody or an antigen-binding fragment thereof according to any one of claims 1 to 13.

15. the antibody or antigen-binding fragment thereof a. A binding affinity (e.g., as measured by surface plasmon resonance, K Ｄ ) binds to human TRDV1 (SEQ ID NO: 272 or 306); b. Optionally, a binding affinity (e.g., as measured by surface plasmon resonance, K Ｄ ) binds to cynomolgus TRDV1 (SEQ ID NO: 308); c. has an IC50 for TCR down-modulation of less than about 50 nM (preferably, less than about 10 nM); d. have an IC50 for killing THP-1 cells of less than about 10 nM (preferably, less than about 5 nM); e. The anti-Vδ1 antibody or antigen-binding fragment thereof of any one of claims 1 to 14, having an IC90 for THP-1 cell killing of less than about 50 nM.

16. The antibody or antigen-binding fragment thereof binds only to an epitope within amino acid residues 1-90 of SEQ ID NO:272, SEQ ID NO:306, and / or SEQ ID NO:308; or b. The antibody or antigen-binding fragment thereof binds only to an epitope within amino acid residues 1-90 of SEQ ID NO:272, SEQ ID NO:306, and / or SEQ ID NO:308; or (i) amino acids 3 to 20 of SEQ ID NO:272, SEQ ID NO:306, and / or SEQ ID NO:308; and / or (ii) binds to an epitope within the region of amino acids 37-77 of SEQ ID NO:272, SEQ ID NO:306, and / or SEQ ID NO:308; An anti-Vδ1 antibody or an antigen-binding fragment thereof according to any one of claims 1 to 15.

17. The anti-Vδ1 antibody or antigen-binding fragment thereof according to any one of claims 1 to 16, wherein the epitope is an activation epitope of a γδ T cell, and optionally binding of the activation epitope (i) downregulates the γδ TCR, (ii) activates degranulation of the γδ T cell, and / or (iii) promotes killing by γδ T cell; and / or upregulates expression of CD107a, CD25, CD69, and / or Ki67.

18. the antibody is a multispecific antibody that specifically binds to the variable δ1 (Vδ1) chain of the γδ T cell receptor (TCR) and a second antigen, the second antigen being a cancer or cancer-associated antigen, an immunomodulatory antigen, or a cluster of differentiation (CD), and optionally The cancer antigen or cancer-associated antigen is selected from the group consisting of AFP, AKAP-4, ALK, α-fetoprotein, androgen receptor, B7H3, BAGE, BCA225, BCAA, Bcr-abl, β-catenin, β-HCG, β-human chorionic gonadotropin, BORIS, BTAA, CA 125, CA 15-3, CA 195, CA 19-9, CA 242, CA 27.29, CA 72-4, CA-50, CAM. 17.1, CAM43, carbonic anhydrase IX, carcinoembryonic antigen, CD22, CD33 / IL3Ra, CD68\P1, CDK4, CEA, chondroitin sulfate proteoglycan 4 (CSPG4), c-Met, CO-029, CSPG4, cyclin B1, cyclophilin C-related protein, CYP1B1, E2A-PRL, EGFR, EGFRvIII, EL F2M, EpCAM, EphA2, ephrin B2, Epstein-Barr virus antigen EBVA, ERG (TMPRSS2ETS fusion gene), ETV6-AML, FAP, FGF-5, Fos-related antigen 1, fucosyl GM1, G250, Ga733\EpCAM, GAGE-1, GAGE-2, GD2, GD3, glioma-associated antigen, GloboH, glycolipid F77, GM3, GP 100, GP 100 (Pmel 17), H4-RET, HER-2 / neu, HER-2 / Neu / ErbB-2, high molecular weight melanoma-associated antigen (HMW-MAA), HPV E6, HPV E7, hTERT, HTgp-175, human telomerase reverse transcriptase, idiotype, IGF-I receptor, IGF-II, IGH-IGK, insulin growth factor (IGF)-I, intestinal carboxylesterase, K-ras, LAGE-1a, LCK, lectin-reactive AFP, legumain, LMP2, M344, MA-50, Mac-2 binding protein, MAD-CT-1, MAD-CT-2, MAGE, MAGE A1, MAGE A3, MAGE-1, MAGE-3, MAGE-4, MAGE-5, MAGE-6, MART-1, MART-1 / MelanA, M-CSF, melanoma-associated chondroitin sulfate proteoglycan (MCSP), mesothelin, MG7-Ag, ML-IAP, MN-CAIX, MOV18, MUC1, Mum-1, hsp70-2, MYCN, MYL-RAR, NA17, NB / 70K, neuronal / glial antigen 2 (NG2), neutrophil elastase, nm-23H1, NuMa, NY-BR-1, NY-CO-1, NY-ESO, NY-ESO-1, NY-ESO-1, OY-TES1, p15, p16, p180erbB3, p185erbB2, p53, p53 mutant, Page4, PAX3, PAX5, PDGFR-β, PLAC1, and polycystine. Alkaline, Prostate Cancer Tumor Antigen-1 (PCTA-1), Prostate Specific Antigen, Prostatic Acid Phosphatase (PAP), Proteinase 3 (PR1), PSA, PSCA, PSMA, RAGE-1, Ras, Ras mutant, RCAS1, RGS5, RhoC, ROR1, RU1, RU2 (AS), SART3, SDCCAG16, sLe(a), sperm protein 17, SSX2, STn, survivin, TA-90, TAAL6, TAG-72, telomerase, thyroglobulin, Tie 2, TLP, Tn, TPS, TRP-1, TRP-2, TRP-2, TSP-180, tyrosinase, VEGF, VEGFR2, VISTA, WT1, XAGE 1, 43-9F, 5T4, and 791Tgp72; The immunomodulatory antigen may be B7-1 (CD80), B7-2 (CD86), B7-DC (CD273), B7-H1 (CD274), B7-H2 (CD275), B7-H3 (CD276), B7-H4 (VTCN). 1), B7-H5 (VISTA), BTLA (CD272), CD137, CD137L, CD24, CD27, CD28, CD38, CD40, CD40L (CD154), CD54, CD59, CD70, C selected from the group consisting of TLA4 (CD152), CXCL9, GITR (CD357), HVEM (CD270), ICAM-1 (CD54), ICOS (CD278), LAG-3 (CD223), OX40 (CD134), OX40L (CD252), PD-1 (CD279), PD-L1 (CD274), TIGIT, CD314, CD334, CD335, CD337, and TIM-3 (CD366); The CD antigen is CD1a, CD1b, CD1c, CD1d, CD1e, CD2, CD3, CD3d, CD3e, CD3g, CD4, CD5, CD6, CD7, CD8, CD8a, CD8b, CD9, CD10, CD11a, CD11b, CD11c, CD11d, CD13, CD14, CD15, CD16, CD16a, CD16b, CD17, CD18, CD19, CD20, CD21, CD22, CD23, CD24, CD25, CD26, CD27, CD28, CD29, CD30, CD31, CD32A, CD32B, CD33, CD34, CD35, CD36, CD37, CD38, CD39, CD40, CD41, CD42, CD42a, CD42b, CD42c, CD42d, CD43, CD44, CD45, CD46, CD47, CD48, CD49a, CD49b, CD49c, CD49d, CD49e, CD49f, CD50, CD51, CD52, CD53, CD54, CD55, CD56, CD57, CD58, CD59, CD60a, CD60b, CD60c, CD61, CD62E, CD62L, CD62P, CD63, CD64a, CD65, CD65s, CD66a, CD66b, CD66c, CD66d, CD66e, CD66f, CD68, CD69, CD70, CD71, CD72, CD73, CD74, CD75, CD75s, CD77, CD79A, CD79B, CD80, CD81, CD82, CD83, CD84, CD85A, CD85B, CD85C, CD85D, CD85F, CD85G, CD85H, CD85I, CD85J, CD85K, CD85M, CD86, CD87, CD88, CD89, CD90, CD91, CD92, CD93, CD94, CD95, CD96, CD97, CD98, CD99, CD100, CD101, CD102, CD103, CD104, CD105, CD106, CD107, CD107a, CD107b, CD108, CD109, CD110, CD111, CD112, CD113, CD114, CD115, CD116, CD117, CD118, CD119, CD120, CD120a, CD120b, CD121a, CD121b, CD122, CD123, CD124, CD125, CD126, CD127, CD129, CD130, CD131, CD132, CD133, CD134, CD135,CD136、CD137、CD138、CD139、CD140A、CD140B、CD141、CD142、CD143、CD144、CDw145、CD146、CD147、CD148、CD150、CD151、CD152、CD153、CD154、CD155、CD156、CD156a、CD156b、CD156c、CD157、CD158、CD158A、CD158B1、CD158B2、CD158C、CD158D、CD158E1、CD158E2、CD158F1、CD158F2、CD158G、CD158H、CD158I、CD158J、CD158K、CD159a、CD159c、CD160、CD161、CD162、CD163、CD164、CD165、CD166、CD167a、CD167b、CD168、CD169、CD170、CD171、CD172a、CD172b、CD172g、CD173、CD174、CD175、CD175s、CD176、CD177、CD178、CD179a、CD179b、CD180、CD181、CD182、CD183、CD184、CD185、CD186、CD187、CD188、CD189、CD190、CD191、CD192、CD193、CD194、CD195、CD196、CD197、CDw198、CDw199、CD200、CD201、CD202b、CD203c、CD204、CD205、CD206、CD207、CD208、CD209、CD210、CDw210a、CDw210b、CD211、CD212、CD213a1、CD213a2、CD214、CD215、CD216、CD217、CD218a、CD218b、CD219、CD220、CD221、CD222、CD223、CD224、CD225、CD226、CD227、CD228、CD229、CD230、CD231、CD232、CD233、CD234、CD235a、CD235b、CD236、CD237、CD238、CD239、CD240CE、CD240D、CD241、CD242、CD243、CD244、CD245、CD246、CD247、CD248、CD249、CD250、CD251、CD252、CD253、CD254、CD255、CD256、CD257、CD258、CD259、CD260、CD261、CD262、CD263、CD264, CD265, CD266, CD267, CD268, CD269, CD270, CD271, CD272, CD273, CD274, CD275, CD276, CD277, C D278, CD279, CD280, CD281, CD282, CD283, CD284, CD285, CD286, CD287, CD288, CD289, CD290, CD291, CD 292, CDw293, CD294, CD295, CD296, CD297, CD298, CD299, CD300A, CD300C, CD301, CD302, CD303, CD304, CD305, CD306, CD307, CD307a, CD307b, CD307c, CD307d, CD307e, CD308, CD309, CD310, CD311, CD312, CD3 13, CD314, CD315, CD316, CD317, CD318, CD319, CD320, CD321, CD322, CD323, CD324, CD325, CD326, CD32 7, CD328, CD329, CD330, CD331, CD332, CD333, CD334, CD335, CD336, CD337, CD338, CD339, CD340, CD344 19. The anti-Vδ1 antibody or antigen-binding fragment thereof according to any one of claims 1 to 18, wherein the antibody or antigen-binding fragment is selected from the group consisting of CD349, CD351, CD352, CD353, CD354, CD355, CD357, CD358, CD360, CD361, CD362, CD363, CD364, CD365, CD366, CD367, CD368, CD369, CD370, and CD371.

19. The anti-Vδ1 antibody or antigen-binding fragment thereof according to any one of claims 1 to 17, wherein the antibody is not a bispecific or multispecific antibody.

20. the antibody is a bispecific antibody, a. the second antigen is CD19, and optionally the antibody comprises SEQ ID NO:314; SEQ ID NO:315; SEQ ID NO:316; SEQ ID NO:396; SEQ ID NO:397; SEQ ID NO:421 and SEQ ID NO:422; SEQ ID NO:504 and SEQ ID NO:422; or SEQ ID NO:423 and SEQ ID NO:424; b. the second antigen is Her2 (CD340), and optionally the antibody comprises SEQ ID NO:393; SEQ ID NO:394; SEQ ID NO:395; SEQ ID NO:398; SEQ ID NO:414 and SEQ ID NO:433; SEQ ID NO:504 and SEQ ID NO:433; SEQ ID NO:505 and SEQ ID NO:433; SEQ ID NO:414 and SEQ ID NO:434; SEQ ID NO:504 and SEQ ID NO:434; or SEQ ID NO:505 and SEQ ID NO:434; c. the second antigen is EGFR, and optionally the antibody comprises SEQ ID NO:378; SEQ ID NO:379; SEQ ID NO:380; SEQ ID NO:382; SEQ ID NO:383; SEQ ID NO:384; SEQ ID NO:385; SEQ ID NO:386; SEQ ID NO:387; SEQ ID NO:388; SEQ ID NO:399; SEQ ID NO:425 and SEQ ID NO:426; SEQ ID NO:421 and SEQ ID NO:437; SEQ ID NO:504 and SEQ ID NO:437; SEQ ID NO:423 and SEQ ID NO:427; SEQ ID NO:425 and SEQ ID NO:428; SEQ ID NO:421 and SEQ ID NO:429; SEQ ID NO:504 and SEQ ID NO:429; SEQ ID NO:423 and SEQ ID NO:430; SEQ ID NO:414 and SEQ ID NO:431; SEQ ID NO:414 and SEQ ID NO:435; SEQ ID NO:504 and SEQ ID NO:431; SEQ ID NO:504 and SEQ ID NO:435; SEQ ID NO:505 and SEQ ID NO:431; or SEQ ID NO:505 and SEQ ID NO:435; d. the second antigen is FAPα, and optionally the antibody comprises SEQ ID NO:401; SEQ ID NO:402; SEQ ID NO:414 and SEQ ID NO:415; SEQ ID NO:504 and SEQ ID NO:415; or SEQ ID NO:505 and SEQ ID NO:415; e. the second antigen is MSLN, and optionally the antibody comprises SEQ ID NO:403; SEQ ID NO:404; SEQ ID NO:414 and SEQ ID NO:416; SEQ ID NO:504 and SEQ ID NO:416; or SEQ ID NO:505 and SEQ ID NO:416; f. the second antigen is PD-1, and optionally the antibody comprises SEQ ID NO: 405; SEQ ID NO: 406; or SEQ ID NO: 438 and SEQ ID NO: 417; g. the second antigen is 4-1BB, and optionally the antibody comprises SEQ ID NO:407; SEQ ID NO:408; or SEQ ID NO:414 and SEQ ID NO:418; SEQ ID NO:504 and SEQ ID NO:418; or SEQ ID NO:505 and SEQ ID NO:418; h. the second antigen is OX40, and optionally the antibody comprises SEQ ID NO:409; SEQ ID NO:410; SEQ ID NO:414 and SEQ ID NO:419; SEQ ID NO:504 and SEQ ID NO:419; or SEQ ID NO:504 and SEQ ID NO:419; or i. The anti-Vδ1 antibody or antigen-binding fragment thereof of any one of claims 1-18, wherein the second antigen is TIGIT, and optionally the antibody comprises SEQ ID NO:411; SEQ ID NO:412; or SEQ ID NO:439 and SEQ ID NO:

420.

21. The anti-Vδ1 antibody or antigen-binding fragment thereof according to any one of claims 1 to 20, wherein the antibody is Fc-enabled.

22. A pharmaceutical composition comprising the antibody or antibody-binding fragment thereof according to any one of claims 1 to 21 and a pharma- ceutically acceptable diluent or carrier.

23. A pharmaceutical composition comprising an anti-Vδ1 antibody or antibody-binding fragment according to any one of claims 1 to 21, or the pharmaceutical composition according to claim 22, for use in treating a disease or disorder in a subject or modulating an immune response in a subject.

24. a. The disease or disorder is cancer, an infectious disease, or an inflammatory disease, or the subject in which the immune response is modulated has cancer, an infectious disease, or an inflammatory disease, or b. The pharmaceutical composition of claim 23, wherein modulating an immune response in a subject comprises at least one selected from the group consisting of activating γδ T cells, inducing or enhancing proliferation of γδ T cells, inducing or enhancing expansion of γδ T cells, inducing or enhancing degranulation of γδ T cells, inducing or enhancing killing activity by γδ T cells, inducing or enhancing cytotoxicity of γδ T cells, inducing or enhancing recruitment of γδ T cells, prolonging survival of γδ T cells, and enhancing resistance to exhaustion of γδ T cells.

25. 25. The pharmaceutical composition of claim 23 or 24, wherein diseased cells are killed and healthy cells are spared.

26. A pharmaceutical composition comprising an anti-TCRδ variable region 1 (anti-Vδ1) antibody or an antigen-binding fragment thereof according to any one of claims 1 to 21, or a pharmaceutical composition according to claim 22, for use in the treatment of cancer, an infectious disease, or an inflammatory disease.